bump pointer: internal (D-319, concept docs, plan rewound-line-freshness, B-bmk)

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

.github/scripts/Get-StorageAuthHeaders.ps1

@@ -11,6 +11,7 @@
     Identity comes from whatever `az login` established: the federated GitHub OIDC principal
     in CI (azure/login, subject repo:okieselbach/AutopilotMonitor:ref:refs/heads/main), the
     operator's own account for the local build. No secret is read, stored or passed around.
+    Under GitHub Actions the token is masked in the run log before it is returned.
 
     x-ms-version is MANDATORY here, not decoration: Entra-authorized requests are rejected
     below 2017-11-09, and Table requests without a SAS must carry the header at all. 2021-08-06
@@ -45,6 +46,15 @@ if ($LASTEXITCODE -ne 0 -or [string]::IsNullOrWhiteSpace($token)) {
            'on the table -- a missing role shows up later as HTTP 403 AuthorizationPermissionMismatch.')
 }
 
+# GitHub masks only secrets.* on its own; a token minted at run time is clear text in the
+# (public) run log the moment anything prints it -- an uncaptured call of this script, or
+# Get-Error / Format-List on a failed request, whose TargetObject carries this header.
+# Write-Host, never Write-Output: the output stream is this script's return value. Only
+# under Actions -- anywhere else the line would print the token instead of hiding it.
+if ($env:GITHUB_ACTIONS -eq 'true') {
+    Write-Host "::add-mask::$token"
+}
+
 return @{
     'Authorization' = "Bearer $token"
     'x-ms-version'  = '2021-08-06'

.github/workflows/deploy-web.yml

@@ -108,6 +108,8 @@ jobs:
           NEXT_PUBLIC_ENTRA_REDIRECT_URI: ${{ vars.NEXT_PUBLIC_ENTRA_REDIRECT_URI }}
           NEXT_PUBLIC_ENTRA_POST_LOGOUT_REDIRECT_URI: ${{ vars.NEXT_PUBLIC_ENTRA_POST_LOGOUT_REDIRECT_URI }}
           NEXT_PUBLIC_API_BASE_URL: ${{ vars.NEXT_PUBLIC_API_BASE_URL }}
+          # Browsers load the live stats through it, and the build reads it once to bake the
+          # numbers of this moment into the landing page's static HTML (lib/platformStats.ts).
           NEXT_PUBLIC_PLATFORM_STATS_MANIFEST_URL: ${{ vars.NEXT_PUBLIC_PLATFORM_STATS_MANIFEST_URL }}
           NEXT_PUBLIC_APPINSIGHTS_CONNECTION_STRING: ${{ secrets.NEXT_PUBLIC_APPINSIGHTS_CONNECTION_STRING }}
           # Build stamp for public/version.json (scripts/generate-version.js in prebuild);
@@ -121,6 +123,9 @@ jobs:
           npm run build
           test -f out/version.json || { echo "out/version.json missing - export did not run"; exit 1; }
           test -f out/whats-new.json || { echo "out/whats-new.json missing - whats-new prebuild did not run"; exit 1; }
+          # Fail-soft like the star count: browsers still load the stats live; only crawlers and
+          # LLM fetchers, which run no JS, see no numbers until the next deploy.
+          grep -q 'data-stats-snapshot=' out/index.html || echo "::warning::Platform stats were not baked into the landing page (reason in the build log) - crawlers and LLM fetchers see no numbers until the next deploy"
 
       # One archive of the exact bytes that get uploaded, so the attestation has a single subject.
       - name: Package export

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerHealthTests.cs

@@ -140,6 +140,22 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             Assert.Equal(1, fired); // the persisted flag suppressed the second emission
         }
 
+        [Fact]
+        public void Registry_reconciliation_counters_survive_a_restart()
+        {
+            using var h = new Harness();
+            h.Tracker.ScriptRuns.CountVerified();
+            h.Tracker.ScriptRuns.CountVerified();
+            h.Tracker.ScriptRuns.CountCorrected();
+            h.Tracker.SaveStateForTest();
+
+            h.Restart();
+
+            var health = h.Tracker.GetHealthSnapshot();
+            Assert.Equal(2, health.PlatformOutputVerified);
+            Assert.Equal(1, health.PlatformOutputCorrected);
+        }
+
         [Fact]
         public async Task Handler_time_does_not_count_against_the_line_budget()
         {

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerOverwriteRewindTests.RetryPairing.cs

@@ -0,0 +1,336 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// B-96m: IME re-runs a failed platform script on later check-ins, so AgentExecutor.log can hold several runs of one
+    /// policy before the tracker has read IME's result of the first — always on the agent's first pass (the agent starts
+    /// mid-enrollment and reads all of AgentExecutor.log before IntuneManagementExtension.log), after a restart, and
+    /// whenever a result line surfaces late. With one slot per policy the second executor start reused the first run's
+    /// slot and its end block overwrote the first one: the first IME result went out with the LAST run's exit code and
+    /// output (session eff1b413: the bootstrap script "Failed (exit 0)" with the stdout of its successful retry), every
+    /// later result without an end block. These tests pin one run per executor start, each IME result paired with the
+    /// run of its policy that started last before it, each run carrying its own end block.
+    /// </summary>
+    public sealed partial class ImeLogTrackerOverwriteRewindTests
+    {
+        private const string RetryPolicyId = "4c2d8e1a-7b3f-4a9e-8d21-6f0b5c3e9a74";
+        private const string RetryUser = "00000000-0000-0000-0000-000000000000";
+
+        private static string ImeEntryAt(string time, string message)
+            => $"<![LOG[{message}]LOG]!><time=\"{time}\" date=\"9-10-2026\" component=\"IntuneManagementExtension\" context=\"\" type=\"1\" thread=\"12\" file=\"\">\r\n";
+
+        /// <summary>One executor run's start block: banner, the platform argument line, paths, launch.</summary>
+        private static string RunStart(string time, string pid, string policyId = RetryPolicyId, string userId = RetryUser)
+        {
+            var path = $@"{ImeDir}\Policies\Scripts\{userId}_{policyId}.ps1";
+            var results = $@"{ImeDir}\Policies\Results\{userId}_{policyId}";
+            return ExecutorBanner(time)
+                + EntryAt(time, $"Adding argument powershell with value {path} to the named argument list.")
+                + EntryAt(time, "Powershell option gets invoked")
+                + EntryAt(time, path)
+                + EntryAt(time, results + ".output")
+                + EntryAt(time, results + ".error")
+                + EntryAt(time, results + ".timeout")
+                + ExecutorLaunch(time, path, pid);
+        }
+
+        /// <summary>
+        /// One executor run's end block in AgentExecutor's order. "error from script =" logs the stderr buffer before the
+        /// output readers finished (<paramref name="stderrSnapshot"/>); "write output done" logs the final texts, the
+        /// error part being exactly the error file IME judges.
+        /// </summary>
+        private static string RunEnd(string time, int exitCode, string stdout, string stderr, string? stderrSnapshot = null)
+            => EntryAt(time, $"Powershell exit code is {exitCode}")
+            + EntryAt(time, $"length of out={stdout.Length}")
+            + EntryAt(time, $"length of error={stderr.Length}")
+            + EntryAt(time, "error from script =" + (stderrSnapshot ?? stderr))
+            + EntryAt(time, exitCode == 0 ? "Powershell script is successfully executed." : "Powershell script is failed to execute")
+            + EntryAt(time, $"write output done. output = {stdout}, error = {stderr}")
+            + EntryAt(time, "Revert Wow64FsRedirection")
+            + EntryAt(time, "Agent executor completed.");
+
+        private static string ImeRunStart(string time, string policyId = RetryPolicyId, string userId = RetryUser)
+            => ImeEntryAt(time, $@"Script file {ImeDir}\Policies\Scripts\{userId}_{policyId}.ps1 is generated.");
+
+        private static string ImeRunResult(string time, string result, string policyId = RetryPolicyId, string userId = RetryUser)
+            => ImeEntryAt(time, $"[PowerShell] User Id = {userId}, Policy id = {policyId}, policy result = {result}");
+
+        private static void AppendImeLog(Harness h, string text)
+            => File.AppendAllText(Path.Combine(Path.GetDirectoryName(h.LogPath)!, "IntuneManagementExtension.log"), text, new UTF8Encoding(false));
+
+        /// <summary>Result | exit | stdout | stderr — readable in an assertion failure; "-" no exit code, "~" never read.</summary>
+        private static string Shape(ScriptExecutionState s)
+            => $"{s.Result}|{(s.ExitCode.HasValue ? s.ExitCode.Value.ToString() : "-")}|{s.Stdout ?? "~"}|{s.Stderr ?? "~"}";
+
+        /// <summary>
+        /// Two poll passes as the agent runs them (read the files, then the flushes), the second past the result hold:
+        /// a result missing its end block goes out by then.
+        /// </summary>
+        private static async Task PassAndSettle(Harness h)
+        {
+            await h.Tracker.RunPollPassAsync(default);
+            h.Now = h.Now.AddSeconds(6);
+            await h.Tracker.RunPollPassAsync(default);
+        }
+
+        [Fact]
+        public async Task First_pass_pairs_each_ime_result_with_the_end_block_of_its_own_run()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            // IME's first run and two retries on later check-ins, all written before the agent started.
+            h.Append(RunStart("12:00:10.0000000", "1001") + RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "1002") + RunEnd("12:10:12.0000000", 1, "Run B output", "")
+                + RunStart("12:20:10.0000000", "1003") + RunEnd("12:20:12.0000000", 0, "Run C output", ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success")
+                + ImeRunStart("12:20:08.0000000") + ImeRunResult("12:20:12.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|1||Run A failed", "Success|1|Run B output|", "Success|0|Run C output|" },
+                h.Completed.Select(Shape).ToArray());
+            Assert.All(h.Completed, s => Assert.Equal("ime_policy_result", s.ResultSource));
+            Assert.True(h.Completed[0].StartedAtUtc < h.Completed[1].StartedAtUtc && h.Completed[1].StartedAtUtc < h.Completed[2].StartedAtUtc);
+            Assert.Equal(3, h.Completed.Select(s => s.RunId).Distinct().Count());
+        }
+
+        [Fact]
+        public async Task Retry_of_the_bootstrap_script_never_lends_its_success_output_to_the_failed_first_attempt()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "2001") + RunEnd("12:00:20.0000000", 1, "attempt 1: download failed", "Invoke-WebRequest : The remote name could not be resolved")
+                + RunStart("12:10:10.0000000", "2002") + RunEnd("12:10:20.0000000", 0, "===== Bootstrap Completed Successfully =====", ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:20.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:20.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[]
+            {
+                "Failed|1|attempt 1: download failed|Invoke-WebRequest : The remote name could not be resolved",
+                "Success|0|===== Bootstrap Completed Successfully =====|",
+            }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Run_killed_at_the_timeout_reports_failed_without_the_next_runs_end_block()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            // IME killed the first executor after 1800 s: its start block is all AgentExecutor.log holds of it.
+            h.Append(RunStart("12:00:10.0000000", "3001")
+                + RunStart("12:40:10.0000000", "3002") + RunEnd("12:40:12.0000000", 0, "Run B output", ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:30:10.5000000", "Failed")
+                + ImeRunStart("12:40:08.0000000") + ImeRunResult("12:40:12.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|-|~|~", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Run_whose_result_never_surfaced_falls_back_on_imes_rule_before_the_next_run()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "4001") + RunEnd("12:00:12.0000000", 0, "Run A output", "Run A wrote an error")
+                + RunStart("12:10:10.0000000", "4002") + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            // Run A's result line was lost; run B's is there.
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|0|Run A output|Run A wrote an error", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+            Assert.Equal(new[] { "agentexecutor_fallback", "ime_policy_result" }, h.Completed.Select(s => s.ResultSource).ToArray());
+        }
+
+        [Fact]
+        public async Task Run_in_flight_survives_the_emit_of_the_run_before_it()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "5001") + RunEnd("12:00:12.0000000", 0, "Run A output", "")
+                + RunStart("12:10:10.0000000", "5002"));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Success") + ImeRunStart("12:10:08.0000000"));
+            await PassAndSettle(h);
+            h.Now = h.Now.AddSeconds(30);
+            await h.Pass();
+
+            // Run B ends minutes later.
+            h.Append(RunEnd("12:10:40.0000000", 0, "Run B output", ""));
+            AppendImeLog(h, ImeRunResult("12:10:40.1000000", "Success"));
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Success|0|Run A output|", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Shutdown_between_the_two_logs_flushes_each_run_with_its_own_end_block()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "6001") + RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "6002") + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            // The pass is cancelled after AgentExecutor.log; the shutdown flush follows.
+            await h.Pass();
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now, force: true);
+
+            h.Restart();
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success"));
+            await PassAndSettle(h);
+
+            // Each run went out with its own block and IME's verdict on it; the results read after the restart are
+            // the same runs and change nothing.
+            Assert.Equal(new[] { "Failed|1||Run A failed", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+            Assert.All(h.Completed, s => Assert.Equal("agentexecutor_fallback", s.ResultSource));
+        }
+
+        [Fact]
+        public async Task End_block_line_recovered_after_the_next_run_started_stays_with_its_own_run()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "7001"));
+            var exitLineAt = h.Length;
+            h.Append(RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "7002") + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            await h.Pass();
+
+            // A stale writer rewrites run A's exit line in place: the ledger check re-reads it behind run B's start.
+            h.Overwrite(exitLineAt, EntryAt("12:00:12.0000000", "Powershell exit code is 7"));
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddSeconds(2);
+            await h.Pass();
+
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success"));
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|7||Run A failed", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Run_without_result_or_end_block_is_dropped_once_a_later_run_has_its_result()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9001")
+                + RunStart("12:10:10.0000000", "9002") + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+            Assert.Equal(0, h.Tracker.ParkedPlatformScriptCountForTest);
+        }
+
+        [Fact]
+        public void Reading_the_same_executor_start_line_again_never_parks_its_run()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            var line = $@"Adding argument powershell with value {ImeDir}\Policies\Scripts\{RetryUser}_{RetryPolicyId}.ps1 to the named argument list.";
+            var at = T0.AddMinutes(-30);
+
+            h.Tracker.ProcessLogMessageForTest(line, at, "AgentExecutor.log");
+            h.Tracker.ProcessLogMessageForTest(line, at, "AgentExecutor.log");
+            Assert.Equal(0, h.Tracker.ParkedPlatformScriptCountForTest);
+
+            h.Tracker.ProcessLogMessageForTest(line, at.AddMinutes(10), "AgentExecutor.log");
+            Assert.Equal(1, h.Tracker.ParkedPlatformScriptCountForTest);
+        }
+
+        [Fact]
+        public async Task Run_without_end_block_keeps_waiting_for_its_result_across_a_shutdown()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9101") + RunStart("12:40:10.0000000", "9102"));
+            await h.Pass();
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now, force: true);
+            Assert.Empty(h.Completed);
+
+            h.Restart();
+            Assert.Equal(1, h.Tracker.ParkedPlatformScriptCountForTest);
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:30:10.5000000", "Failed"));
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|-|~|~" }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Earlier_run_emitted_while_a_later_one_runs_never_takes_the_later_runs_register_entry()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9201") + RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "9202"));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed") + ImeRunStart("12:10:08.0000000"));
+            await PassAndSettle(h);
+            Assert.Single(h.Completed);
+
+            // A save of this key is the latest run's, and that one is still running.
+            h.Tracker.ScriptRuns.NotePassCompleted(h.Now);
+            Assert.Equal(PlatformRunClaim.Wait, h.Tracker.ScriptRuns.TryClaim(RetryUser, RetryPolicyId, h.Now.AddSeconds(-10), out _));
+
+            h.Append(RunEnd("12:10:40.0000000", 0, "Run B output", ""));
+            AppendImeLog(h, ImeRunResult("12:10:40.1000000", "Success"));
+            await PassAndSettle(h);
+            h.Tracker.ScriptRuns.NotePassCompleted(h.Now);
+
+            Assert.Equal(PlatformRunClaim.Claimed, h.Tracker.ScriptRuns.TryClaim(RetryUser, RetryPolicyId, h.Now.AddSeconds(-10), out var run));
+            Assert.Equal(h.Completed[1].RunId, run!.RunId);
+            Assert.Equal("Run B output", run.Stdout);
+        }
+
+        [Fact]
+        public async Task Run_of_another_user_keeps_its_own_register_entry_when_it_waited_for_its_result()
+        {
+            const string otherUser = "2b7e5c91-3d4a-4f80-b6e2-9a1c7d3f5e08";
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9301") + RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "9302", userId: otherUser));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000", userId: otherUser));
+            await PassAndSettle(h);
+            h.Tracker.ScriptRuns.NotePassCompleted(h.Now);
+
+            Assert.Equal(PlatformRunClaim.Claimed, h.Tracker.ScriptRuns.TryClaim(RetryUser, RetryPolicyId, h.Now.AddSeconds(-10), out var run));
+            Assert.Equal(h.Completed[0].RunId, run!.RunId);
+            Assert.Equal(PlatformRunClaim.Wait, h.Tracker.ScriptRuns.TryClaim(otherUser, RetryPolicyId, h.Now.AddSeconds(-10), out _));
+        }
+
+        [Fact]
+        public async Task Start_line_read_again_stays_a_late_line_after_an_earlier_run_of_another_user_went_out()
+        {
+            const string otherUser = "2b7e5c91-3d4a-4f80-b6e2-9a1c7d3f5e08";
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9401") + RunEnd("12:00:12.0000000", 0, "Run A output", "")
+                + RunStart("12:10:10.0000000", "9402", userId: otherUser) + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            // Run A's result surfaces after run B's (its line was hidden by a concurrent writer).
+            AppendImeLog(h, ImeRunResult("12:10:12.1000000", "Success", userId: otherUser) + ImeRunResult("12:00:12.1000000", "Success"));
+            await PassAndSettle(h);
+            Assert.Equal(new[] { "Success|0|Run B output|", "Success|0|Run A output|" }, h.Completed.Select(Shape).ToArray());
+
+            // Run B's executor start line read again (a rewind): a late line of the emitted run B, never a new run.
+            var started = 0;
+            h.Tracker.OnScriptStarted = _ => started++;
+            h.Tracker.ProcessLogMessageForTest(
+                $@"Adding argument powershell with value {ImeDir}\Policies\Scripts\{otherUser}_{RetryPolicyId}.ps1 to the named argument list.",
+                h.Completed[0].StartedAtUtc, "AgentExecutor.log");
+            Assert.Equal(0, started);
+        }
+
+        [Fact]
+        public async Task Final_stderr_of_the_end_block_replaces_the_early_snapshot_even_without_stdout()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            // The snapshot was taken before the error reader finished; IME judged the full error file.
+            h.Append(RunStart("12:00:10.0000000", "8001") + RunEnd("12:00:12.0000000", 0, "", "Remove-AppxPackage : Cannot process argument", stderrSnapshot: ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|0||Remove-AppxPackage : Cannot process argument" }, h.Completed.Select(Shape).ToArray());
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerOverwriteRewindTests.RewindFreshness.cs

@@ -0,0 +1,139 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.SignalAdapters;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// Sessions d29e27e3 and 4377911b: a concurrent IME writer overwrote the result line of a platform script, and the
+    /// overwrite check recovered it one pass later. Recovered lines were never fresh, so they resolved in the agent's own
+    /// cached zone (+60) instead of anchoring themselves (+120): the end stamp landed an hour ahead of the clock and the
+    /// run duration was omitted. Bytes that read differently at a position than at the last look were written after that
+    /// look, so when the replaced bytes were confirmed seconds ago the new line's age is bounded like an appended line's —
+    /// these tests pin that it anchors itself then, and only then.
+    /// </summary>
+    public sealed partial class ImeLogTrackerOverwriteRewindTests
+    {
+        private static void AppendExecutorLog(Harness h, string text)
+            => File.AppendAllText(Path.Combine(Path.GetDirectoryName(h.LogPath)!, "AgentExecutor.log"), text, new UTF8Encoding(false));
+
+        /// <summary>An IME log entry with the byte length of <paramref name="sameLengthAs"/>: what a stale writer's line replaces exactly.</summary>
+        private static string FillerLike(string time, string sameLengthAs)
+        {
+            var bare = ImeEntryAt(time, "[Win32App] checking ");
+            Assert.True(sameLengthAs.Length > bare.Length);
+            return ImeEntryAt(time, "[Win32App] checking " + new string('x', sameLengthAs.Length - bare.Length));
+        }
+
+        /// <summary>
+        /// A platform run whose IME writer lives in +120 (local = UTC + 2 h; the harness clock is 19:30Z): both logs are
+        /// observed empty first, so what follows is read fresh. Returns the IME log position where the filler line sits.
+        /// </summary>
+        private static async Task<long> StartRunAndReadFiller(Harness h, string fillerTime, string resultEntry)
+        {
+            h.Append(string.Empty);
+            AppendExecutorLog(h, string.Empty);
+            await h.Tracker.RunPollPassAsync(default);
+
+            AppendExecutorLog(h, RunStart("21:29:50.0000000", "1001"));
+            h.Append(ImeRunStart("21:29:48.0000000"));
+            await h.Tracker.RunPollPassAsync(default);
+
+            // Another IME writer appends a line; the tracker reads it.
+            var at = h.Length;
+            h.Append(FillerLike(fillerTime, resultEntry));
+            h.Now = h.Now.AddSeconds(1);
+            await h.Tracker.RunPollPassAsync(default);
+            return at;
+        }
+
+        [Fact]
+        public async Task Result_line_recovered_seconds_after_its_bytes_were_read_anchors_itself_like_a_fresh_line()
+        {
+            using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            var result = ImeRunResult("21:30:01.1000000", "Success");
+            var at = await StartRunAndReadFiller(h, "21:30:00.5000000", result);
+
+            // The script ends: its end block, then the stale IME service writes the result over the filler.
+            AppendExecutorLog(h, RunEnd("21:30:01.0000000", 0, "done", ""));
+            h.Overwrite(at, result);
+            h.Now = h.Now.AddSeconds(1);
+            await PassAndSettle(h);
+
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(CmTraceOffsetOrigin.LineAnchored, script.ResultProvenance!.Origin);
+            Assert.Equal(120, script.ResultProvenance.OffsetMinutes);
+            Assert.Equal(ImeLogTrackerAdapter.DurationPairVerdict.Verified, ImeLogTrackerAdapter.JudgeDurationPair(
+                script.StartedAtProvenance, script.ResultProvenance, false, script.ResultObservedAtUtc!.Value - script.StartedAtUtc!.Value, out _));
+        }
+
+        [Fact]
+        public async Task Verification_passes_keep_the_replaced_bytes_current_for_a_script_that_runs_longer()
+        {
+            using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            var result = ImeRunResult("21:30:41.1000000", "Success");
+            var at = await StartRunAndReadFiller(h, "21:30:00.5000000", result);
+
+            // The script runs 40 s; the cadence check verifies the ledger every 10 s while the run is in flight.
+            for (var i = 0; i < 4; i++)
+            {
+                h.Now = h.Now.AddSeconds(10);
+                await h.Tracker.RunPollPassAsync(default);
+            }
+
+            AppendExecutorLog(h, RunEnd("21:30:41.0000000", 0, "done", ""));
+            h.Overwrite(at, result);
+            h.Now = h.Now.AddSeconds(1);
+            await PassAndSettle(h);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(CmTraceOffsetOrigin.LineAnchored, script.ResultProvenance!.Origin);
+            Assert.Equal(120, script.ResultProvenance.OffsetMinutes);
+        }
+
+        [Fact]
+        public async Task Overwrite_does_not_move_the_files_measured_writer_offset()
+        {
+            using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            var result = ImeRunResult("21:30:01.1000000", "Success");
+            var at = await StartRunAndReadFiller(h, "21:30:00.5000000", result);
+            Assert.True(h.Tracker.OffsetCalibrator.TryGetOffset("IntuneManagementExtension.log", out var before));
+
+            AppendExecutorLog(h, RunEnd("21:30:01.0000000", 0, "done", ""));
+            h.Overwrite(at, result);
+            h.Now = h.Now.AddSeconds(1);
+            await PassAndSettle(h);
+
+            Assert.True(h.Tracker.OffsetCalibrator.TryGetOffset("IntuneManagementExtension.log", out var after));
+            Assert.Equal(before, after);
+        }
+
+        [Theory]
+        // Replaced bytes confirmed 1 s / 30 s ago: written since, age bounded like an appended line's.
+        [InlineData(true, true, 1, true)]
+        [InlineData(true, true, 30, true)]
+        // Confirmed longer ago: the new bytes could be minutes old — their age may round onto the 15-minute grid.
+        [InlineData(true, true, 31, false)]
+        // The clock stepped back since the confirmation: the age is unknown.
+        [InlineData(true, true, -1, false)]
+        // The divergence lies in bytes the ledger never held (dropped by a cap): nothing dates them.
+        [InlineData(true, false, 1, false)]
+        // The pass itself is not fresh — the first pass after a restart never anchors.
+        [InlineData(false, true, 1, false)]
+        // Nothing was replaced.
+        [InlineData(true, true, null, false)]
+        public void Rewound_entry_is_fresh_only_when_the_bytes_it_replaced_were_confirmed_within_the_fresh_window(
+            bool passLinesAreFresh, bool entryAtRewindPointReplaced, int? secondsSinceConfirmed, bool expected)
+        {
+            var now = new DateTime(2026, 10, 4, 19, 2, 0, DateTimeKind.Utc);
+            DateTime? confirmed = secondsSinceConfirmed.HasValue ? now.AddSeconds(-secondsSinceConfirmed.Value) : (DateTime?)null;
+            Assert.Equal(expected, ImeLogTracker.RewoundEntryIsFresh(passLinesAreFresh, entryAtRewindPointReplaced, confirmed, now));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerOverwriteRewindTests.WriterBoundary.cs

@@ -0,0 +1,368 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// Session 756970cf: IME launched a Win32 detection executor and a platform-script executor 15 ms apart, and both
+    /// opened AgentExecutor.log at the same end-of-file offset. The platform executor's shorter start block overwrote
+    /// the detection executor's, whose identity line the tracker never saw; the detection's end block (exit 1 and its
+    /// stdout), written at its own position behind its own start block, then sat behind the PLATFORM start block, and
+    /// "the nearest preceding marker owns the line" handed another script's output and exit code to the platform
+    /// script. These tests pin the writer boundary: an entry that is not exactly one CMTrace record is where one
+    /// writer's bytes end and another's begin, and nothing behind it belongs to the invocation in front of it.
+    /// </summary>
+    public sealed partial class ImeLogTrackerOverwriteRewindTests
+    {
+        private const string RaceUserId = "00000000-0000-0000-0000-000000000000";
+        private const string RacePlatformId = "1d6f0a52-3c4e-4b7a-9e21-5f8c7d2b9a10";
+        private const string RaceDetectionAppId = "8b2e4c71-6a9d-4f03-b5e8-2c7a1d9f4e36";
+        private const string RaceFillerAppId = "5e1c2b7d-0a4f-4c8e-9d36-7b2f1e8a4c50";
+        private const string ImeDir = @"C:\Program Files (x86)\Microsoft Intune Management Extension";
+        private const string DetectionStdout = "VERBOSE: === Sample Suite Detection Started ===\r\nWARNING: === DETECTION FAILED: Sample Suite is not installed ===";
+        private const string PlatformStdout = "=== bootstrap loader started ===\r\nInstaller finished (exit code 0).";
+
+        private static string EntryAt(string time, string message)
+            => $"<![LOG[{message}]LOG]!><time=\"{time}\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">\r\n";
+
+        /// <summary>The four lines every AgentExecutor invocation starts with — identical length for every executor.</summary>
+        private static string ExecutorBanner(string time)
+            => EntryAt(time, "ExecutorLog AgentExecutor gets invoked")
+            + EntryAt(time, "Creating command line parser, name delimiter is - and value separator is  .")
+            + EntryAt(time, "Getting Ordered Parameters")
+            + EntryAt(time, "Parsing Ordered Parameters.");
+
+        private static string ExecutorLaunch(string time, string scriptPath, string pid)
+            => EntryAt(time, "Prepare to run Powershell Script ..")
+            + EntryAt(time, $"cmd line for running powershell is -NoProfile -executionPolicy bypass -file  \"{scriptPath}\" ")
+            + EntryAt(time, "runAs32BitOn64 = False, so Disable Wow64FsRedirection")
+            + EntryAt(time, @"PowerShell path is C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe")
+            + EntryAt(time, $"[Executor] created powershell with process id {pid}");
+
+        private static string PlatformStartBlock(string time, string policyId, string pid)
+        {
+            var path = $@"{ImeDir}\Policies\Scripts\{RaceUserId}_{policyId}.ps1";
+            var results = $@"{ImeDir}\Policies\Results\{RaceUserId}_{policyId}";
+            return ExecutorBanner(time)
+                + EntryAt(time, $"Adding argument powershell with value {path} to the named argument list.")
+                + EntryAt(time, "Powershell option gets invoked")
+                + EntryAt(time, path)
+                + EntryAt(time, results + ".output")
+                + EntryAt(time, results + ".error")
+                + EntryAt(time, results + ".timeout")
+                + ExecutorLaunch(time, path, pid);
+        }
+
+        private static string DetectionStartBlock(string time, string appId, string pid)
+        {
+            var path = $@"{ImeDir}\Content\DetectionScripts\{appId}_2.ps1";
+            return ExecutorBanner(time)
+                + EntryAt(time, $"Adding argument powershellDetection with value {path} to the named argument list.")
+                + EntryAt(time, "PowershellDetection option gets invoked")
+                + EntryAt(time, path)
+                + EntryAt(time, path + "quotedResultFilePath.txt")
+                + EntryAt(time, path + "quotedErrorFilePath.txt")
+                + EntryAt(time, path + "quotedTimeoutFilePath.txt")
+                + EntryAt(time, path + "quotedExitCodeFilePath.txt")
+                + ExecutorLaunch(time, path, pid);
+        }
+
+        private static string ExecutorEndBlock(string time, int exitCode, string stdout)
+            => EntryAt(time, $"Powershell exit code is {exitCode}")
+            + EntryAt(time, $"length of out={stdout.Length}")
+            + EntryAt(time, "length of error=0")
+            + EntryAt(time, "error from script =")
+            + EntryAt(time, exitCode == 0 ? "Powershell script is successfully executed." : "Powershell script is failed to execute")
+            + EntryAt(time, $"write output done. output = {stdout}, error = ")
+            + EntryAt(time, "Revert Wow64FsRedirection")
+            + EntryAt(time, "Agent executor completed.");
+
+        private static string PlatformResultLine(string policyId)
+            => $"[PowerShell] User Id = {RaceUserId}, Policy id = {policyId}, policy result = Success";
+
+        /// <summary>The file offsets at which the entries of an ASCII <paramref name="block"/> start when it is written at <paramref name="at"/>.</summary>
+        private static HashSet<long> EntryStarts(string block, long at)
+        {
+            Assert.True(block.All(c => c < 128), "offset arithmetic assumes ASCII test content");
+            var starts = new HashSet<long>();
+            for (var i = block.IndexOf("<![LOG[", StringComparison.Ordinal); i >= 0; i = block.IndexOf("<![LOG[", i + 1, StringComparison.Ordinal))
+                starts.Add(at + i);
+            return starts;
+        }
+
+        [Fact]
+        public async Task Executor_that_opened_at_the_same_offset_never_lends_its_end_block_to_the_platform_script()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+
+            // An earlier, finished detection run: the race starts mid-file like in the field log.
+            h.Append(DetectionStartBlock("12:00:00.0000000", RaceFillerAppId, "1548") + ExecutorEndBlock("12:00:00.5000000", 0, "detected"));
+            await h.Pass();
+            var x = h.Length;
+
+            // Detection executor C and platform executor D open the file at the same end x. C writes first; the tracker
+            // reads C's banner, then D writes its own start block over C's.
+            var cStart = DetectionStartBlock("12:00:01.0000000", RaceDetectionAppId, "6416");
+            var dStart = PlatformStartBlock("12:00:01.2000000", RacePlatformId, "2524");
+            var cHead = cStart.Substring(0, cStart.IndexOf("<![LOG[Getting Ordered Parameters", StringComparison.Ordinal));
+            h.Append(cHead);
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Append(cStart.Substring(cHead.Length));
+            h.Overwrite(x, dStart);
+
+            // The field geometry: D's start block is shorter and ends inside one of C's lines, so the tail of that line
+            // sits between D's start block and C's remaining bytes.
+            Assert.True(dStart.Length < cStart.Length);
+            Assert.DoesNotContain(x + dStart.Length, EntryStarts(cStart, x));
+            h.Now = h.Now.AddMilliseconds(150);
+            await h.Pass();
+            Assert.True(h.Health.OverwriteRewinds >= 1);
+
+            // C ends: its end block lands at its own position, right behind its own (overwritten) start block.
+            Assert.Equal(x + cStart.Length, h.Length);
+            var cEnd = ExecutorEndBlock("12:00:07.0000000", 1, DetectionStdout);
+            h.Append(cEnd);
+            h.Now = h.Now.AddSeconds(6);
+            await h.Pass();
+
+            // IME's result for D reaches the tracker before D's own end block: the completion must wait for it.
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId), sourceFileName: "IntuneManagementExtension.log");
+            Assert.Empty(h.Completed);
+
+            // D ends: its end block lands at ITS position, over the fragment and C's bytes; C's last line survives.
+            var dEnd = ExecutorEndBlock("12:00:09.5000000", 0, PlatformStdout);
+            Assert.True(dEnd.Length < cStart.Length - dStart.Length + cEnd.Length);
+            h.Overwrite(x + dStart.Length, dEnd);
+            h.Now = h.Now.AddMilliseconds(130);
+            await h.Pass();
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(RacePlatformId, script.PolicyId);
+            Assert.Equal("Success", script.Result);
+            Assert.Equal(0, script.ExitCode);
+            Assert.Equal(PlatformStdout.Replace("\r\n", "\n"), script.Stdout);
+            Assert.DoesNotContain(h.Completed, s => (s.Stdout ?? string.Empty).Contains("Detection"));
+
+            // The run is known to the registry reconciliation under the user id of its own lines (D-316).
+            Assert.Equal(RaceUserId, script.UserId);
+            Assert.False(string.IsNullOrEmpty(script.RunId));
+            h.Tracker.ScriptRuns.NotePassCompleted(DateTime.MaxValue.AddDays(-1));
+            Assert.Equal(PlatformRunClaim.Claimed, h.Tracker.ScriptRuns.TryClaim(RaceUserId, RacePlatformId, h.Now, out var run));
+            Assert.Equal(script.RunId, run!.RunId);
+        }
+
+        /// <summary>
+        /// The mirror image: a foreign executor whose stream position lies inside the platform start block (it opened
+        /// at the same end with a shorter start block) writes its end block there. Its first line merges with the head of
+        /// a platform line — cut inside the message or inside the trailer, which the parser would otherwise read up to
+        /// the foreign trailer — and its output line follows without any marker in between.
+        /// </summary>
+        [Theory]
+        [InlineData(15)]
+        [InlineData(-30)]
+        public async Task Foreign_end_block_merged_into_the_platform_start_block_never_reaches_the_platform_script(int cut)
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(DetectionStartBlock("12:00:00.0000000", RaceFillerAppId, "1548") + ExecutorEndBlock("12:00:00.5000000", 0, "detected"));
+            await h.Pass();
+            var x = h.Length;
+
+            var dStart = PlatformStartBlock("12:00:01.0000000", RacePlatformId, "2524");
+            h.Append(dStart);
+            await h.Pass();
+
+            // The foreign end block starts inside the line after D's argument line.
+            var lineAfterArgument = x + dStart.IndexOf("<![LOG[Powershell option gets invoked", StringComparison.Ordinal);
+            var lineLength = EntryAt("12:00:01.0000000", "Powershell option gets invoked").Length;
+            var at = lineAfterArgument + (cut > 0 ? cut : lineLength + cut);
+            var foreignEnd = ExecutorEndBlock("12:00:03.0000000", 1, "foreign output");
+            Assert.True(at + foreignEnd.Length < x + dStart.Length, "the foreign block must end inside D's start block");
+            h.Overwrite(at, foreignEnd);
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId), sourceFileName: "IntuneManagementExtension.log");
+            h.Now = h.Now.Add(ImeLogTracker.PlatformScriptEndBlockGrace);
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            // No owner is provable behind the cut: the completion goes out without end-block data, never with the foreign one.
+            var script = Assert.Single(h.Completed);
+            Assert.Equal("Success", script.Result);
+            Assert.Null(script.ExitCode);
+            Assert.Null(script.Stdout);
+        }
+
+        [Fact]
+        public async Task Entry_read_unchanged_after_a_rewind_keeps_its_platform_marker()
+        {
+            const string platformId = "2b7d9e41-8c3a-4f60-a5d2-9e1b7c4f3a08";
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+
+            // Detection W waits for its script; detection X runs completely behind it; platform F starts behind X.
+            var wStart = DetectionStartBlock("12:00:00.0000000", RaceFillerAppId, "1111");
+            var xRun = DetectionStartBlock("12:00:00.2000000", RaceDetectionAppId, "2222") + ExecutorEndBlock("12:00:00.4000000", 0, "x detected");
+            h.Append(wStart + xRun + PlatformStartBlock("12:00:01.0000000", platformId, "3333"));
+            await h.Pass();
+
+            // W ends at its own position, over the head of X's run; F's start block keeps its bytes and offset.
+            var wEnd = ExecutorEndBlock("12:00:02.0000000", 0, "w detected");
+            Assert.True(wEnd.Length < xRun.Length);
+            h.Overwrite(wStart.Length, wEnd);
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+
+            // F's end block lands behind its start block: still F's, because F's marker survived with its bytes.
+            h.Append(ExecutorEndBlock("12:00:05.0000000", 7, "Hello from F"));
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(platformId), sourceFileName: "IntuneManagementExtension.log");
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(platformId, script.PolicyId);
+            Assert.Equal(7, script.ExitCode);
+            Assert.Equal("Hello from F", script.Stdout);
+        }
+
+        [Fact]
+        public async Task Writer_boundary_read_unchanged_after_a_rewind_still_closes_the_platform_invocation()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+
+            // Detection Q waits for its script while detection R runs completely behind it.
+            var qStart = DetectionStartBlock("12:00:00.0000000", RaceFillerAppId, "1111");
+            var rRun = DetectionStartBlock("12:00:00.2000000", "6c3f8a20-1d5e-4b97-8f4a-0e2d6b9c7a13", "2222") + ExecutorEndBlock("12:00:00.4000000", 0, "r detected");
+            h.Append(qStart + rRun);
+            await h.Pass();
+            var x = h.Length;
+
+            // The race of the field case behind them: the boundary closes D.
+            var cStart = DetectionStartBlock("12:00:01.0000000", RaceDetectionAppId, "6416");
+            var dStart = PlatformStartBlock("12:00:01.2000000", RacePlatformId, "2524");
+            h.Append(cStart);
+            h.Overwrite(x, dStart);
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            // Q ends at its own position, over R's run: the rewind starts in front of the race, whose bytes read unchanged.
+            var qEnd = ExecutorEndBlock("12:00:02.0000000", 0, "q detected");
+            Assert.True(qEnd.Length < rRun.Length);
+            h.Overwrite(qStart.Length, qEnd);
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            // C's end block behind the boundary stays unowned; D's own end block completes D.
+            var cEnd = ExecutorEndBlock("12:00:07.0000000", 1, DetectionStdout);
+            h.Append(cEnd);
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId), sourceFileName: "IntuneManagementExtension.log");
+            Assert.Empty(h.Completed);
+
+            h.Overwrite(x + dStart.Length, ExecutorEndBlock("12:00:09.5000000", 0, PlatformStdout));
+            h.Now = h.Now.AddMilliseconds(130);
+            await h.Pass();
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(0, script.ExitCode);
+            Assert.Equal(PlatformStdout.Replace("\r\n", "\n"), script.Stdout);
+        }
+
+        [Fact]
+        public async Task Raw_text_in_the_executor_log_is_never_matched_and_closes_the_platform_invocation()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(PlatformStartBlock("12:00:00.0000000", RacePlatformId, "2524"));
+            await h.Pass();
+
+            // The tail of a cut line that happens to read like an exit line, then a foreign end block.
+            h.Append("Powershell exit code is 5\r\n" + ExecutorEndBlock("12:00:02.0000000", 6, "foreign output"));
+            // A fragment right at the bookmark stops the first pass for a check; the second one reads it.
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId), sourceFileName: "IntuneManagementExtension.log");
+            h.Now = h.Now.Add(ImeLogTracker.PlatformScriptEndBlockGrace);
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Null(script.ExitCode);
+            Assert.Null(script.Stdout);
+        }
+
+        [Fact]
+        public async Task Fragment_in_the_ime_log_does_not_close_the_platform_run_context()
+        {
+            using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            // In the IME log the service writes the platform marker and the context line itself; the fragment in
+            // between is the tail of an executor's telemetry line and separates nothing.
+            h.Append(Entry(@"Script file C:\Program Files (x86)\Microsoft Intune Management Extension\Policies\Scripts\" + RaceUserId + "_" + RacePlatformId + ".ps1 is generated.", "17")
+                + "ing mananger...]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">\r\n"
+                + Entry("Launch powershell executor in user session", "17"));
+            await h.Pass();
+
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId));
+            h.Now = h.Now.Add(ImeLogTracker.PlatformScriptEndBlockGrace);
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal("User", script.RunContext);
+        }
+
+        [Fact]
+        public async Task Cut_multi_line_output_adds_one_boundary_not_one_per_line()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(PlatformStartBlock("12:00:00.0000000", RacePlatformId, "2524"));
+            await h.Pass();
+            var markersBefore = h.Tracker.InvocationMarkerCountForTest("AgentExecutor.log");
+
+            var lines = string.Concat(Enumerable.Range(1, 600).Select(i => $"orphaned output line {i}\r\n"));
+            h.Append(lines);
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            Assert.Equal(markersBefore + 1, h.Tracker.InvocationMarkerCountForTest("AgentExecutor.log"));
+        }
+
+        [Theory]
+        [InlineData("<![LOG[Powershell exit code is 0]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", true)]
+        [InlineData("<![LOG[write output done. output = line one\nline two, error = ]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", true)]
+        [InlineData("\uFEFF<![LOG[ExecutorLog AgentExecutor gets invoked]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", true)]
+        [InlineData("t code is 3]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", false)]
+        [InlineData("", false)]
+        [InlineData("<![LOG[Powe<![LOG[Powershell exit code is 1]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", false)]
+        [InlineData("<![LOG[Powershell option gets invoked]LOG]!><time=\"12:00:00.0000000\" da<![LOG[Powershell exit code is 1]LOG]!><time=\"12:00:01.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", false)]
+        [InlineData("<![LOG[write output done. output = line one\nline<![LOG[Agent executor completed.]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", false)]
+        public void Single_cmtrace_record_is_told_apart_from_the_cut_of_two_writers(string text, bool expected)
+        {
+            Assert.Equal(expected, ImeLogTracker.IsSingleCmTraceRecord(text));
+        }
+
+        [Theory]
+        [InlineData("AgentExecutor.log", true)]
+        [InlineData("AgentExecutor-20261003-233348.log", true)]
+        [InlineData("IntuneManagementExtension.log", false)]
+        [InlineData("IntuneManagementExtension-20261003-233348.log", false)]
+        [InlineData("HealthScripts.log", false)]
+        [InlineData("AppWorkload.log", false)]
+        public void Writer_boundaries_apply_to_the_executor_log_live_and_rotated(string fileName, bool expected)
+        {
+            Assert.Equal(expected, ImeLogTracker.IsWriterBoundaryLogFile(fileName));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerOverwriteRewindTests.cs

@@ -25,7 +25,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
     /// contract: unchanged bytes never rewind, changed bytes are processed exactly once, and the
     /// executor lines a rewind uncovers belong to the invocation that owns their file position.
     /// </summary>
-    public sealed class ImeLogTrackerOverwriteRewindTests
+    public sealed partial class ImeLogTrackerOverwriteRewindTests
     {
         private static readonly DateTime T0 = new DateTime(2026, 9, 10, 19, 30, 0, DateTimeKind.Utc);
 
@@ -42,7 +42,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
         private static readonly string[] ScriptPatternIds =
         {
             "PS-AGENT-INVOCATION", "PS-AGENT-ARG", "PS-AGENT-SCRIPT-START", "PS-AGENT-EXITCODE",
-            "PS-AGENT-OUTPUT", "PS-AGENT-COMPLETED", "PS-SCRIPT-GENERATED", "PS-SCRIPT-CONTEXT", "PS-SCRIPT-RESULT",
+            "PS-AGENT-OUTPUT", "PS-AGENT-ERROR", "PS-AGENT-COMPLETED", "PS-SCRIPT-GENERATED", "PS-SCRIPT-CONTEXT", "PS-SCRIPT-RESULT",
         };
 
         /// <summary>The shipped pattern JSON — the same source combine.js embeds — so the contract is the real one.</summary>
@@ -502,6 +502,10 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
         public async Task Ime_result_line_hidden_by_an_executor_start_line_is_recovered_from_the_ime_log()
         {
             using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            // Seen empty first: the start lines are fresh and anchor themselves like the recovered result line will,
+            // so start and result sit on one timeline whatever the host's own zone is.
+            h.Append(string.Empty);
+            await h.Pass();
             h.Append(Entry(GeneratedLine, "17") + Entry("Launch powershell executor in user session", "17") + Entry("process id = 10608", "17"));
             await h.Pass();
             var servicePosition = h.Length;

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerPlatformScriptFallbackTests.cs

@@ -83,8 +83,33 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             Assert.Single(emitted);
         }
 
+        [Theory]
+        // IME's verdict is Success exactly when the error file is empty, whatever the exit code. Judged by the exit
+        // code, session 67ae751c showed exit 0 with the script's own stderr as Success, and 46a41a0a an exit 1 without
+        // stderr as Failed, a run IME reported as Success one cycle earlier.
+        [InlineData(0, "Invoke-WebRequest : The remote name could not be resolved", "Failed")]
+        [InlineData(1, "", "Success")]
+        [InlineData(1, "  \n", "Success")]
+        [InlineData(0, "", "Success")]
+        [InlineData(1, null, "Failed")]
+        [InlineData(0, null, "Success")]
+        public void Fallback_judges_like_ime_by_the_stderr_it_read(int exitCode, string? stderr, string expected)
+        {
+            using var tmp = new TempDirectory();
+            var tracker = BuildTracker(tmp, out var emitted);
+            var observedAt = new DateTime(2026, 6, 19, 12, 59, 4, DateTimeKind.Utc);
+
+            tracker.SeedPendingPlatformScriptForTesting("0d2294bf", exitCode: exitCode, exitObservedAtUtc: observedAt, stderr: stderr);
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
+
+            var script = Assert.Single(emitted);
+            Assert.Equal(expected, script.Result);
+            Assert.Equal(exitCode, script.ExitCode);
+            Assert.Equal("agentexecutor_fallback", script.ResultSource);
+        }
+
         [Fact]
-        public void Nonzero_exit_code_emits_failed_result()
+        public void Nonzero_exit_code_without_a_stderr_line_emits_failed_result()
         {
             using var tmp = new TempDirectory();
             var tracker = BuildTracker(tmp, out var emitted);

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerScriptStatePersistenceTests.cs

@@ -108,6 +108,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
 
             var tracker = BuildTracker(tmp, out var emitted);
             tracker.LoadStateForTest(); // must not throw
+            Assert.Equal(0, tracker.ParkedPlatformScriptCountForTest);
 
             // Degrades to pre-fix behavior: no markers restored, normal emission works (the
             // result waits for its end block until the shutdown flush).
@@ -116,6 +117,32 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             Assert.Single(emitted);
         }
 
+        [Fact]
+        public void Pending_slot_from_a_state_file_without_executor_start_loads_and_completes()
+        {
+            using var tmp = new TempDirectory();
+            var started = new DateTime(2026, 10, 4, 9, 0, 0, DateTimeKind.Utc);
+
+            // A pending slot written by an agent before runs carried their executor start and run id.
+            var persistence = new ImeTrackerStatePersistence(tmp.Path, new AgentLogger(tmp.Path, AgentLogLevel.Info));
+            persistence.Save(new ImeTrackerStateData
+            {
+                PendingPlatformScripts = new List<ScriptExecutionState>
+                {
+                    new ScriptExecutionState { PolicyId = "policyF", ScriptType = "platform", StartedAtUtc = started, ExitCode = 0, ExitObservedAtUtc = started.AddSeconds(5), Stdout = "done", Stderr = "" },
+                },
+            });
+
+            var tracker = BuildTracker(tmp, out var emitted);
+            tracker.LoadStateForTest();
+            tracker.CompletePlatformScriptFromImeResultForTesting("policyF", "Success", started.AddSeconds(6));
+
+            var script = Assert.Single(emitted);
+            Assert.Equal("Success", script.Result);
+            Assert.Equal(0, script.ExitCode);
+            Assert.False(string.IsNullOrEmpty(script.RunId));
+        }
+
         [Fact]
         public void Stale_result_older_than_current_run_start_is_dropped()
         {

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/ImeRegistryScriptResultObserverTests.cs

@@ -0,0 +1,411 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using AutopilotMonitor.DecisionCore.Engine;
+using Xunit;
+using SharedEventTypes = AutopilotMonitor.Shared.Constants.EventTypes;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
+{
+    /// <summary>
+    /// D-316: IME saves every platform script's result under Policies\&lt;user&gt;\&lt;policy&gt; after reporting the
+    /// batch; the observer checks the tracker's emitted run against it. The field case (session 756970cf): the run
+    /// had been given a Win32 detection script's end block — exit 1 and "Detection Started" output — while IME saved
+    /// the bootstrap output of the platform script itself.
+    /// </summary>
+    public sealed class ImeRegistryScriptResultObserverTests
+    {
+        private const string DeviceUser = "00000000-0000-0000-0000-000000000000";
+        private const string PolicyA = "1d6f0a52-3c4e-4b7a-9e21-5f8c7d2b9a10";
+        private const string PolicyB = "2b7d9e41-8c3a-4f60-a5d2-9e1b7c4f3a08";
+        private const string OwnStdout = "=== bootstrap loader started ===\nInstaller finished (exit code 0).";
+        private const string ForeignStdout = "VERBOSE: === Sample Suite Detection Started ===\nWARNING: === DETECTION FAILED ===";
+        private static readonly DateTime T0 = new DateTime(2026, 10, 3, 20, 59, 0, DateTimeKind.Utc);
+
+        // ── PlatformOutputJudge ─────────────────────────────────────────────────
+
+        private static PlatformScriptRun Run(string? stdout, string? stderr = null, int? exitCode = 0, string result = "Success", string resultSource = "ime_policy_result")
+            => new PlatformScriptRun { PolicyId = PolicyA, UserId = DeviceUser, RunId = "run-1", Emitted = true, Result = result, ResultSource = resultSource, ExitCode = exitCode, Stdout = stdout, Stderr = stderr };
+
+        private static string Details(string executionMessage)
+            => "{\"Version\":1,\"SigningCode\":15,\"EncryptionCode\":19,\"ExecutionMsg\":" + System.Text.Json.JsonSerializer.Serialize(executionMessage) + "}";
+
+        private static SavedScriptResult Saved(string? executionMessage, string result = "Success", int errorCode = 0, string user = DeviceUser, string policy = PolicyA, string stamp = "10/3/2026 9:00:00 PM")
+            => new SavedScriptResult
+            {
+                UserId = user,
+                PolicyId = policy,
+                Result = result,
+                ErrorCode = errorCode,
+                ResultDetails = executionMessage == null ? null : Details(executionMessage),
+                LastUpdatedTimeUtc = stamp,
+            };
+
+        [Fact]
+        public void Field_case_detection_output_on_the_platform_run_is_foreign_and_the_saved_stdout_replaces_it()
+        {
+            var judgement = PlatformOutputJudge.Judge(Run(ForeignStdout, string.Empty, exitCode: 1), Saved(OwnStdout.Replace("\n", "\r\n")));
+            Assert.Equal(PlatformOutputVerdict.Foreign, judgement.Verdict);
+            Assert.Equal("stdout_differs", judgement.Reason);
+            Assert.Equal(OwnStdout, judgement.Stdout);
+            Assert.Equal(string.Empty, judgement.Stderr);
+        }
+
+        [Fact]
+        public void Matching_output_is_verified_across_line_ending_and_trim_differences()
+        {
+            var judgement = PlatformOutputJudge.Judge(Run(OwnStdout, string.Empty), Saved("  " + OwnStdout.Replace("\n", "\r\n") + "\r\n"));
+            Assert.Equal(PlatformOutputVerdict.Verified, judgement.Verdict);
+        }
+
+        [Fact]
+        public void Output_cut_by_the_tracker_is_verified_against_the_longer_saved_text()
+        {
+            var full = string.Concat(Enumerable.Repeat("line of output\n", 1000)).TrimEnd();
+            var emitted = ImeLogTracker.TruncateOutput(full);
+            Assert.EndsWith(ImeLogTracker.OutputTruncationMarker, emitted);
+            Assert.Equal(PlatformOutputVerdict.Verified, PlatformOutputJudge.Judge(Run(emitted), Saved(full)).Verdict);
+        }
+
+        [Fact]
+        public void Both_empty_is_verified_but_stderr_on_a_success_is_another_executors()
+        {
+            Assert.Equal(PlatformOutputVerdict.Verified, PlatformOutputJudge.Judge(Run(string.Empty), Saved(string.Empty)).Verdict);
+            var judgement = PlatformOutputJudge.Judge(Run(string.Empty, "Get-Item : not found"), Saved(string.Empty));
+            Assert.Equal(PlatformOutputVerdict.Foreign, judgement.Verdict);
+            Assert.Equal("stderr_on_success", judgement.Reason);
+        }
+
+        [Fact]
+        public void Explicitly_empty_emitted_output_against_saved_text_is_foreign()
+        {
+            Assert.Equal(PlatformOutputVerdict.Foreign, PlatformOutputJudge.Judge(Run(string.Empty), Saved(OwnStdout)).Verdict);
+            Assert.Equal(PlatformOutputVerdict.Foreign, PlatformOutputJudge.Judge(Run(OwnStdout), Saved(string.Empty)).Verdict);
+        }
+
+        [Fact]
+        public void Output_never_read_is_completed_from_the_saved_text_and_the_exit_code_stands()
+        {
+            var judgement = PlatformOutputJudge.Judge(Run(null), Saved(OwnStdout));
+            Assert.Equal(PlatformOutputVerdict.Repaired, judgement.Verdict);
+            Assert.Equal("stdout_missing", judgement.Reason);
+            Assert.Equal(OwnStdout, judgement.Stdout);
+            Assert.Equal(PlatformOutputVerdict.NotComparable, PlatformOutputJudge.Judge(Run(null), Saved(string.Empty)).Verdict);
+        }
+
+        [Fact]
+        public void Stdout_containing_the_output_error_separator_is_repaired_not_foreign()
+        {
+            // "write output done. output = X, error = " with X = "Copying files, error = 0 errors\nDone": the
+            // lazy split leaves "Copying files" as stdout and the rest as stderr.
+            var judgement = PlatformOutputJudge.Judge(
+                Run("Copying files", "0 errors\nDone, error ="),
+                Saved("Copying files, error = 0 errors\r\nDone"));
+            Assert.Equal(PlatformOutputVerdict.Repaired, judgement.Verdict);
+            Assert.Equal("stdout_split", judgement.Reason);
+            Assert.Equal("Copying files, error = 0 errors\nDone", judgement.Stdout);
+            Assert.Equal(string.Empty, judgement.Stderr);
+        }
+
+        [Fact]
+        public void A_prefix_without_the_split_explanation_is_foreign()
+        {
+            Assert.Equal(PlatformOutputVerdict.Foreign, PlatformOutputJudge.Judge(Run("Detected"), Saved("Detected and repaired")).Verdict);
+        }
+
+        [Fact]
+        public void Failed_with_stderr_is_judged_on_stderr()
+        {
+            Assert.Equal(PlatformOutputVerdict.Verified,
+                PlatformOutputJudge.Judge(Run("partial", "Access denied", 1, "Failed"), Saved("Access denied\r\n", "Failed", 99)).Verdict);
+
+            var missing = PlatformOutputJudge.Judge(Run(null, null, 1, "Failed"), Saved("Access denied", "Failed", 99));
+            Assert.Equal(PlatformOutputVerdict.Repaired, missing.Verdict);
+            Assert.Null(missing.Stdout);
+            Assert.Equal("Access denied", missing.Stderr);
+
+            var foreign = PlatformOutputJudge.Judge(Run("Detected", string.Empty, 0, "Failed"), Saved("Access denied", "Failed", 99));
+            Assert.Equal(PlatformOutputVerdict.Foreign, foreign.Verdict);
+            Assert.Equal(string.Empty, foreign.Stdout);
+            Assert.Equal("Access denied", foreign.Stderr);
+        }
+
+        [Fact]
+        public void Results_without_saved_output_or_from_another_run_are_not_compared()
+        {
+            Assert.Equal("no_saved_output", PlatformOutputJudge.Judge(Run(OwnStdout, null, 1, "Failed"), Saved("1", "Failed", 1)).Reason);
+            var hashMismatch = new SavedScriptResult { UserId = DeviceUser, PolicyId = PolicyA, Result = "Failed", ErrorCode = 2, ResultDetails = "Hash mismatch" };
+            Assert.Equal("no_execution_message", PlatformOutputJudge.Judge(Run(OwnStdout, null, 1, "Failed"), hashMismatch).Reason);
+            Assert.Equal("result_differs", PlatformOutputJudge.Judge(Run(OwnStdout), Saved("Access denied", "Failed", 99)).Reason);
+            // A result derived from the exit code (fallback) is not IME's — the saved one is.
+            Assert.Equal(PlatformOutputVerdict.Verified,
+                PlatformOutputJudge.Judge(Run(OwnStdout, null, 1, "Failed", "agentexecutor_fallback"), Saved(OwnStdout)).Verdict);
+        }
+
+        // ── PlatformScriptRunRegister ───────────────────────────────────────────
+
+        private static ScriptExecutionState Emitted(string policyId, string? stdout, int? exitCode = 0, string? userId = DeviceUser, string runId = "run-1")
+            => new ScriptExecutionState { PolicyId = policyId, ScriptType = "platform", UserId = userId, RunId = runId, Result = "Success", ResultSource = "ime_policy_result", ExitCode = exitCode, Stdout = stdout };
+
+        [Fact]
+        public void A_save_is_paired_only_after_the_tracker_read_past_it_and_the_run_was_emitted()
+        {
+            var runs = new PlatformScriptRunRegister();
+            runs.NoteStarted(DeviceUser, PolicyA, T0);
+            var seen = T0.AddSeconds(30);
+
+            Assert.Equal(PlatformRunClaim.Wait, runs.TryClaim(DeviceUser, PolicyA, seen, out _));
+            runs.NotePassCompleted(seen.AddSeconds(1));
+            Assert.Equal(PlatformRunClaim.Wait, runs.TryClaim(DeviceUser, PolicyA, seen, out _)); // pass started too early
+            runs.NotePassCompleted(seen + PlatformScriptRunRegister.TrackerCatchUp);
+            Assert.Equal(PlatformRunClaim.Wait, runs.TryClaim(DeviceUser, PolicyA, seen, out _)); // run not emitted yet
+
+            runs.NoteEmitted(Emitted(PolicyA, OwnStdout), T0.AddSeconds(40));
+            Assert.Equal(PlatformRunClaim.Claimed, runs.TryClaim(DeviceUser, PolicyA, seen, out var run));
+            Assert.Equal("run-1", run!.RunId);
+            Assert.Equal(OwnStdout, run.Stdout);
+            Assert.Equal(PlatformRunClaim.None, runs.TryClaim(DeviceUser, PolicyA, seen, out _)); // never twice
+        }
+
+        [Fact]
+        public void A_new_start_replaces_the_latest_run_of_its_key_and_other_users_stay_apart()
+        {
+            var runs = new PlatformScriptRunRegister();
+            runs.NoteStarted(DeviceUser, PolicyA, T0);
+            runs.NoteEmitted(Emitted(PolicyA, "first run"), T0.AddSeconds(5));
+            runs.NoteStarted(DeviceUser, PolicyA, T0.AddMinutes(30));
+            runs.NoteEmitted(Emitted(PolicyA, "second run", runId: "run-2"), T0.AddMinutes(30).AddSeconds(5));
+            const string user = "6c3f8a20-1d5e-4b97-8f4a-0e2d6b9c7a13";
+            runs.NoteStarted(user, PolicyA, T0.AddMinutes(31));
+            runs.NotePassCompleted(T0.AddHours(1));
+
+            Assert.Equal(PlatformRunClaim.Claimed, runs.TryClaim(DeviceUser, PolicyA, T0.AddMinutes(31), out var run));
+            Assert.Equal("second run", run!.Stdout);
+            Assert.Equal(PlatformRunClaim.Wait, runs.TryClaim(user, PolicyA, T0.AddMinutes(32), out _));
+            Assert.Equal(PlatformRunClaim.None, runs.TryClaim(DeviceUser, PolicyB, T0.AddMinutes(32), out _));
+        }
+
+        [Fact]
+        public void A_run_without_a_readable_user_id_is_claimed_by_its_policy()
+        {
+            var runs = new PlatformScriptRunRegister();
+            runs.NoteStarted(null, PolicyA, T0);
+            runs.NoteEmitted(Emitted(PolicyA, OwnStdout, userId: null), T0.AddSeconds(5));
+            runs.NotePassCompleted(T0.AddMinutes(5));
+            Assert.Equal(PlatformRunClaim.Claimed, runs.TryClaim(DeviceUser, PolicyA, T0.AddMinutes(1), out _));
+        }
+
+        [Fact]
+        public void Register_keeps_the_newest_runs_and_its_counters_report_each_change_once()
+        {
+            var runs = new PlatformScriptRunRegister();
+            for (var i = 0; i <= PlatformScriptRunRegister.MaxRuns; i++)
+                runs.NoteStarted(DeviceUser, Guid.NewGuid().ToString("D"), T0.AddSeconds(i));
+            runs.NoteStarted(DeviceUser, PolicyA, T0.AddHours(1));
+            runs.NoteEmitted(Emitted(PolicyA, OwnStdout), T0.AddHours(1));
+            runs.NotePassCompleted(T0.AddHours(2));
+            Assert.Equal(PlatformRunClaim.Claimed, runs.TryClaim(DeviceUser, PolicyA, T0.AddHours(1), out _));
+
+            Assert.False(runs.ConsumeCountersChanged());
+            runs.CountVerified();
+            runs.CountCorrected();
+            Assert.True(runs.ConsumeCountersChanged());
+            Assert.False(runs.ConsumeCountersChanged());
+            Assert.Equal(1, runs.Verified);
+            runs.RestoreCounters(7, 3);
+            Assert.Equal(7, runs.Verified);
+            Assert.Equal(3, runs.Corrected);
+        }
+
+        // ── observer flow ───────────────────────────────────────────────────────
+
+        private sealed class Fixture
+        {
+            public readonly FakeSignalIngressSink Sink = new FakeSignalIngressSink();
+            public readonly VirtualClock Clock = new VirtualClock(T0);
+            public readonly PlatformScriptRunRegister Runs = new PlatformScriptRunRegister();
+            public Dictionary<string, SavedScriptResult> Registry = new Dictionary<string, SavedScriptResult>(StringComparer.OrdinalIgnoreCase);
+            public readonly ImeRegistryScriptResultObserver Observer;
+
+            public Fixture()
+            {
+                Observer = new ImeRegistryScriptResultObserver(Runs, new InformationalEventPost(Sink, Clock), null, Clock,
+                    () => new Dictionary<string, SavedScriptResult>(Registry, StringComparer.OrdinalIgnoreCase));
+            }
+
+            public void Save(SavedScriptResult saved) => Registry[ImeRegistryScriptResultObserver.KeyOf(saved.UserId, saved.PolicyId)] = saved;
+
+            /// <summary>The tracker emitted a run, then kept polling past the save.</summary>
+            public void EmitRun(string policyId, string? stdout, int? exitCode, string runId)
+            {
+                Runs.NoteStarted(DeviceUser, policyId, Clock.UtcNow);
+                Runs.NoteEmitted(Emitted(policyId, stdout, exitCode, runId: runId), Clock.UtcNow);
+            }
+
+            public void TrackerCaughtUp() => Runs.NotePassCompleted(Clock.UtcNow);
+
+            public IReadOnlyList<FakeSignalIngressSink.PostedSignal> Corrections()
+                => Sink.Posted.Where(p => p.Payload != null
+                    && p.Payload.TryGetValue(SignalPayloadKeys.EventType, out var et)
+                    && et == SharedEventTypes.ScriptOutputReconciliation).ToList();
+        }
+
+        [Fact]
+        public void Field_case_end_to_end_the_save_corrects_the_run_with_a_warning_naming_it()
+        {
+            var f = new Fixture();
+            f.Save(Saved("an older run of another policy", policy: PolicyB, stamp: "10/2/2026 8:00:00 AM"));
+            f.Observer.Tick("baseline");
+
+            f.EmitRun(PolicyA, ForeignStdout, 1, "run-a");
+            f.Save(Saved(OwnStdout));
+            f.Clock.Advance(TimeSpan.FromSeconds(1));
+            f.Observer.Tick("registry_change");
+            Assert.Empty(f.Corrections()); // the tracker has not read past the save yet
+
+            f.Clock.Advance(PlatformScriptRunRegister.TrackerCatchUp);
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            var correction = Assert.Single(f.Corrections());
+            var data = correction.Payload!;
+            Assert.Equal(PolicyA, data["policyId"]);
+            Assert.Equal("platform", data["scriptType"]);
+            Assert.Equal("run-a", data["runId"]);
+            Assert.Equal("foreign", data["outcome"]);
+            Assert.Equal("stdout_differs", data["reason"]);
+            Assert.Equal("Success", data["result"]);
+            Assert.Equal(OwnStdout, data["stdout"]);
+            Assert.Equal(string.Empty, data["stderr"]);
+            Assert.Equal("1", data["previousExitCode"]);
+            Assert.Equal("0", data["registryErrorCode"]);
+            Assert.Equal("Warning", data[SignalPayloadKeys.Severity]);
+            Assert.Equal("true", data[SignalPayloadKeys.ImmediateUpload]);
+            Assert.DoesNotContain("exitCode", data.Keys);
+            Assert.Equal(1, f.Runs.Corrected);
+            Assert.Equal(0, f.Runs.Verified);
+
+            // The same save read again changes nothing.
+            f.Clock.Advance(TimeSpan.FromMinutes(1));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+            Assert.Single(f.Corrections());
+        }
+
+        [Fact]
+        public void Confirmed_output_is_counted_and_emits_nothing()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            f.EmitRun(PolicyA, OwnStdout, 0, "run-a");
+            f.Save(Saved(OwnStdout));
+            f.Clock.Advance(TimeSpan.FromSeconds(1));
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(TimeSpan.FromSeconds(3));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            Assert.Empty(f.Corrections());
+            Assert.Equal(1, f.Runs.Verified);
+        }
+
+        [Fact]
+        public void Completed_output_is_an_info_event_that_keeps_the_exit_code()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            f.EmitRun(PolicyA, null, 0, "run-a");
+            f.Save(Saved(OwnStdout));
+            f.Clock.Advance(TimeSpan.FromSeconds(1));
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(TimeSpan.FromSeconds(3));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            var data = Assert.Single(f.Corrections()).Payload!;
+            Assert.Equal("repaired", data["outcome"]);
+            Assert.Equal("Info", data[SignalPayloadKeys.Severity]);
+            Assert.DoesNotContain("previousExitCode", data.Keys);
+        }
+
+        [Fact]
+        public void A_save_seen_before_its_run_was_emitted_waits_for_the_emit()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            f.Runs.NoteStarted(DeviceUser, PolicyA, f.Clock.UtcNow); // result held for its end block
+            f.Save(Saved(OwnStdout));
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(TimeSpan.FromSeconds(3));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+            Assert.Equal(0, f.Runs.Verified + f.Runs.Corrected);
+
+            f.Runs.NoteEmitted(Emitted(PolicyA, ForeignStdout, 1, runId: "run-a"), f.Clock.UtcNow);
+            f.Clock.Advance(TimeSpan.FromSeconds(60));
+            f.Observer.Tick("periodic");
+            Assert.Equal("foreign", Assert.Single(f.Corrections()).Payload!["outcome"]);
+        }
+
+        [Fact]
+        public void A_save_no_run_claims_within_the_expiry_is_dropped()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            f.Save(Saved(OwnStdout));
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(ImeRegistryScriptResultObserver.PendingExpiry);
+            f.TrackerCaughtUp();
+            f.Runs.NoteStarted(DeviceUser, PolicyA, f.Clock.UtcNow);
+            f.Observer.Tick("periodic"); // waits for the emit — and expires
+
+            f.Runs.NoteEmitted(Emitted(PolicyA, ForeignStdout, 1, runId: "run-a"), f.Clock.UtcNow);
+            f.Clock.Advance(TimeSpan.FromSeconds(60));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+            Assert.Empty(f.Corrections());
+        }
+
+        [Fact]
+        public void Saves_from_before_the_agent_started_are_the_silent_baseline()
+        {
+            var f = new Fixture();
+            f.EmitRun(PolicyA, ForeignStdout, 1, "run-a");
+            f.Save(Saved(OwnStdout));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("baseline");
+            f.Clock.Advance(TimeSpan.FromMinutes(1));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            Assert.Empty(f.Corrections());
+            Assert.Equal(0, f.Runs.Verified + f.Runs.Corrected);
+        }
+
+        [Fact]
+        public void Corrections_beyond_the_cap_are_counted_but_not_emitted()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            var policies = Enumerable.Range(0, ImeRegistryScriptResultObserver.MaxCorrectionsPerSession + 3).Select(_ => Guid.NewGuid().ToString("D")).ToList();
+            foreach (var policy in policies)
+            {
+                f.EmitRun(policy, ForeignStdout, 1, "run-" + policy);
+                f.Save(Saved(OwnStdout, policy: policy));
+            }
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(TimeSpan.FromSeconds(3));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            Assert.Equal(ImeRegistryScriptResultObserver.MaxCorrectionsPerSession, f.Corrections().Count);
+            Assert.Equal(policies.Count, f.Runs.Corrected);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/SignalAdapters/ImeLogTrackerAdapterPlatformRunTests.cs

@@ -0,0 +1,54 @@
+using System;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.SignalAdapters;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using SharedEventTypes = AutopilotMonitor.Shared.Constants.EventTypes;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.SignalAdapters
+{
+    /// <summary>
+    /// D-316: every emitted platform-script completion carries a run id, and the tracker's run register holds what
+    /// was emitted for it under the IME user id — what the registry reconciliation pairs IME's saved result with.
+    /// </summary>
+    public sealed class ImeLogTrackerAdapterPlatformRunTests
+    {
+        private static readonly DateTime ClockNow = new DateTime(2026, 10, 3, 21, 0, 0, DateTimeKind.Utc);
+        private const string DeviceUser = "00000000-0000-0000-0000-000000000000";
+        private const string PolicyId = "1d6f0a52-3c4e-4b7a-9e21-5f8c7d2b9a10";
+
+        [Fact]
+        public void Platform_completion_carries_its_run_id_and_the_register_holds_the_emitted_run()
+        {
+            using var f = new ImeLogTrackerAdapterFixture(ClockNow);
+            using var adapter = new ImeLogTrackerAdapter(f.Tracker, f.Ingress, f.Clock);
+
+            f.Tracker.LastMatchedLogTimestamp = ClockNow.AddSeconds(-10);
+            f.Tracker.HandlePlatformScriptStarted(PolicyId, "ime", DeviceUser);
+            f.Tracker.RecordPlatformScriptExitCodeForTesting(PolicyId, 0, ClockNow.AddSeconds(-1));
+            f.Tracker.LastMatchedLogTimestamp = ClockNow;
+            f.Tracker.CompletePlatformScriptFromImeResultForTesting(PolicyId, "Success", ClockNow);
+
+            var info = f.InfoEvent(SharedEventTypes.ScriptCompleted);
+            Assert.True(Guid.TryParse(info.Payload!["runId"], out _));
+
+            f.Tracker.ScriptRuns.NotePassCompleted(ClockNow.AddMinutes(1));
+            Assert.Equal(PlatformRunClaim.Claimed, f.Tracker.ScriptRuns.TryClaim(DeviceUser, PolicyId, ClockNow.AddSeconds(5), out var run));
+            Assert.Equal(info.Payload["runId"], run!.RunId);
+            Assert.Equal(0, run.ExitCode);
+            Assert.Equal("Success", run.Result);
+        }
+
+        [Theory]
+        [InlineData("[PowerShell] User Id = 00000000-0000-0000-0000-000000000000, Policy id = d94468af-6ebe-4e94-9901-2a62d33ea6c1, policy result = Success", "00000000-0000-0000-0000-000000000000")]
+        [InlineData(@"Adding argument powershell with value C:\Program Files (x86)\Microsoft Intune Management Extension\Policies\Scripts\6C3F8A20-1D5E-4B97-8F4A-0E2D6B9C7A13_d94468af-6ebe-4e94-9901-2a62d33ea6c1.ps1", "6c3f8a20-1d5e-4b97-8f4a-0e2d6b9c7a13")]
+        [InlineData(@"Script file C:\Program Files (x86)\Microsoft Intune Management Extension\Policies\Scripts\00000000-0000-0000-0000-000000000000_d94468af-6ebe-4e94-9901-2a62d33ea6c1.ps1 is generated", "00000000-0000-0000-0000-000000000000")]
+        [InlineData(@"Adding argument powershellDetection with value C:\Program Files (x86)\Microsoft Intune Management Extension\Content\DetectionScripts\8b2e4c71-6a9d-4f03-b5e8-2c7a1d9f4e36_2.ps1", null)]
+        [InlineData("[PowerShell] User Id = not-a-guid, Policy id = d94468af", null)]
+        [InlineData("", null)]
+        public void Ime_user_id_is_read_from_the_result_line_and_the_script_path(string text, string? expected)
+        {
+            Assert.Equal(expected, ImeLogTracker.ImeUserIdFrom(text));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/Ime/ImeLogTracker.Handlers.cs

@@ -271,17 +271,42 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             }
             else
             {
-                HandlePlatformScriptStarted(id, source);
+                HandlePlatformScriptStarted(id, source, ImeUserIdFrom(match.Value));
             }
         }
 
+        /// <summary>
+        /// The IME user id on a platform-script line — <c>User Id = {id}</c> on the result line,
+        /// <c>…\Policies\Scripts\{id}_{policy}.ps1</c> on the start lines — or null. Read from the
+        /// matched text, not from a capture group, so it works with every pattern pack the agent may
+        /// be served.
+        /// </summary>
+        internal static string ImeUserIdFrom(string text)
+        {
+            if (string.IsNullOrEmpty(text)) return null;
+            const string resultTag = "User Id = ";
+            const string pathTag = @"\Policies\Scripts\";
+            var i = text.IndexOf(resultTag, StringComparison.OrdinalIgnoreCase);
+            if (i >= 0) return GuidAt(text, i + resultTag.Length);
+            i = text.IndexOf(pathTag, StringComparison.OrdinalIgnoreCase);
+            return i >= 0 ? GuidAt(text, i + pathTag.Length) : null;
+        }
+
+        private static string GuidAt(string text, int start)
+        {
+            if (start + 36 > text.Length) return null;
+            var candidate = text.Substring(start, 36);
+            return Guid.TryParse(candidate, out _) ? candidate.ToLowerInvariant() : null;
+        }
+
         // Platform script: AgentExecutor.log entries create/enrich, IME log entries also create.
         // Internal so the stale-slot hardening is directly testable (the public path arrives via
         // a regex Match).
-        internal void HandlePlatformScriptStarted(string id, string source = null)
+        internal void HandlePlatformScriptStarted(string id, string source = null, string userId = null)
         {
             var currentStartTs = LastMatchedLogTimestamp ?? UtcNowProvider();
             var currentStartProvenance = CaptureLastMatchedProvenance();
+            var fromExecutor = string.Equals(source, "agentexecutor", StringComparison.OrdinalIgnoreCase);
 
             // A start line older than the result this policy already emitted is the late start
             // line of THAT run: its AgentExecutor block surfaced after the IME result — the two
@@ -294,7 +319,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             // never tie; a low-resolution clock in a test may).
             if (_platformScriptResultEmitted.TryGetValue(id, out var emittedResultTs) && currentStartTs < emittedResultTs)
             {
-                RecordInvocationMarker(id, isClose: false);
+                RecordInvocationMarker(id, isClose: false, EmittedRunId);
                 NoteInvocationActivity();
                 _logger.Debug($"ImeLogTracker: platform script start line for {id} (source: {source ?? "ime"}) predates its emitted result — late line of that run, not a new one");
                 return;
@@ -302,7 +327,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
 
             if (_pendingPlatformScripts.TryGetValue(id, out var pendingSlot))
             {
-                if (pendingSlot.StartedAtUtc.HasValue && currentStartTs - pendingSlot.StartedAtUtc.Value > TimeSpan.FromHours(24))
+                if (pendingSlot.StartedAtUtc.HasValue && currentStartTs - pendingSlot.StartedAtUtc.Value > StalePlatformRunAge)
                 {
                     // Stale-slot hardening (session eaf3d8c4): a replayed start line from a previous
                     // enrollment whose matching result never appeared (script was mid-run when that
@@ -319,6 +344,15 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                     // Emit what the held run has; its end block did not surface in time.
                     EmitPlatformScriptResult(pendingSlot, "the next run of this policy started");
                 }
+                else if (fromExecutor && LastMatchedLogTimestamp.HasValue && pendingSlot.Result == null
+                    && pendingSlot.ExecutorStartedAtUtc.HasValue && pendingSlot.ExecutorStartedAtUtc.Value < currentStartTs)
+                {
+                    // Every executor process writes its start line once: a later one is the next run
+                    // (IME re-runs a failed script on a later check-in), whose end block must not
+                    // overwrite this one's. This run waits for its IME result — on the first pass
+                    // AgentExecutor.log is read in full before the IME log (session eff1b413).
+                    ParkPlatformRun(pendingSlot);
+                }
                 else if (!pendingSlot.StartedAtUtc.HasValue)
                 {
                     // The slot was opened by its result while the start block was still hidden;
@@ -328,7 +362,16 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                     _stateDirty = true;
                 }
             }
-            if (!_pendingPlatformScripts.ContainsKey(id))
+            if (_pendingPlatformScripts.TryGetValue(id, out var slot))
+            {
+                if (slot.UserId == null && userId != null) slot.UserId = userId;
+                if (fromExecutor && !slot.ExecutorStartedAtUtc.HasValue)
+                {
+                    slot.ExecutorStartedAtUtc = currentStartTs;
+                    _stateDirty = true;
+                }
+            }
+            else
             {
                 // A fresh start for this policy (no pending entry) begins a NEW execution.
                 // Clear any emitted-marker from a prior run so IME re-evaluations / retries of
@@ -336,24 +379,29 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                 // deduped away. A start line of the emitted run itself never reaches this point
                 // (the guard above), so this never clears the current run's own marker.
                 _platformScriptResultEmitted.Remove(id);
-                _pendingPlatformScripts[id] = new ScriptExecutionState
+                slot = new ScriptExecutionState
                 {
                     PolicyId = id,
                     ScriptType = "platform",
+                    UserId = userId,
+                    RunId = NewRunId(),
                     // Prefer the source CMTrace timestamp so a script that started before the
                     // agent launched (replayed log content) is dated to its real start, not now.
                     // Set only at slot creation: the start line fires twice (agentexecutor + ime
                     // source) but the earliest wins.
                     StartedAtUtc = currentStartTs,
                     StartedAtProvenance = currentStartProvenance,
+                    ExecutorStartedAtUtc = fromExecutor ? currentStartTs : (DateTime?)null,
                 };
+                _pendingPlatformScripts[id] = slot;
+                ScriptRuns.NoteStarted(userId, id, UtcNowProvider());
                 // Live "running" indicator — same signal health scripts emit. Gated on slot
                 // creation so the duplicate start line (agentexecutor + ime source) doesn't
                 // double-emit for the same execution.
                 try { OnScriptStarted?.Invoke(new ScriptStartedInfo { PolicyId = id, ScriptType = "platform" }); }
                 catch (Exception ex) { _logger.Warning($"ImeLogTracker: OnScriptStarted handler threw: {ex.Message}"); }
             }
-            RecordInvocationMarker(id, isClose: false);
+            RecordInvocationMarker(id, isClose: false, LastMatchedLogTimestamp.HasValue ? RunIdOfStartLine(slot, fromExecutor, currentStartTs) : slot.RunId);
             NoteInvocationActivity();
             // Started lines fire twice per script (agentexecutor + ime source) and carry no
             // outcome — the matching `platform script completed` line below carries result+exit
@@ -361,6 +409,34 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             _logger.Debug($"ImeLogTracker: platform script started: {id} (source: {source ?? "ime"})");
         }
 
+        /// <summary>How long after IME's "Script file … is generated" line its executor writes its start line (about 2 s).</summary>
+        private static readonly TimeSpan ImeLaunchWindow = TimeSpan.FromMinutes(1);
+
+        /// <summary>
+        /// The run a timestamped start line belongs to, for its invocation marker. An executor start line belongs to the
+        /// slot unless it is older than the slot's executor start — re-read behind a later run — then to the parked run
+        /// it started. IME's "Script file … is generated" precedes its executor: it belongs to the live run whose
+        /// executor started within <see cref="ImeLaunchWindow"/> after it, else to a slot whose executor has not
+        /// started yet; otherwise its run is not known (yet) and the lines behind it go nowhere.
+        /// </summary>
+        private string RunIdOfStartLine(ScriptExecutionState slot, bool fromExecutor, DateTime lineTs)
+        {
+            if (fromExecutor)
+            {
+                if (!slot.ExecutorStartedAtUtc.HasValue || slot.ExecutorStartedAtUtc.Value <= lineTs) return slot.RunId;
+                var parked = _parkedPlatformScripts.FirstOrDefault(r =>
+                    string.Equals(r.PolicyId, slot.PolicyId, StringComparison.OrdinalIgnoreCase) && r.ExecutorStartedAtUtc == lineTs);
+                return parked?.RunId ?? EmittedRunId;
+            }
+
+            var launched = LivePlatformRuns(slot.PolicyId)
+                .Where(r => r.ExecutorStartedAtUtc.HasValue && r.ExecutorStartedAtUtc.Value >= lineTs && r.ExecutorStartedAtUtc.Value - lineTs <= ImeLaunchWindow)
+                .OrderBy(r => r.ExecutorStartedAtUtc.Value)
+                .FirstOrDefault();
+            if (launched != null) return launched.RunId;
+            return slot.ExecutorStartedAtUtc.HasValue ? EmittedRunId : slot.RunId;
+        }
+
         // Routes line-by-line script-data handlers (context / exitCode / output) to the right
         // accumulator based on the pattern's scriptType parameter. Health-script lines feed the
         // single-slot _pendingHealthScript (the HS-NEW-RESULT JSON delivers the full cycle in one
@@ -439,6 +515,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                 ApplyExitCode(script, exitCode, LastMatchedLogTimestamp ?? UtcNowProvider(), CaptureLastMatchedProvenance());
             else if (ownerPolicyId != null)
                 _logger.Debug($"ImeLogTracker: exit code {exitCode} belongs to platform script {ownerPolicyId}, whose completion was already emitted — dropped");
+            else
+                LogLineBehindWriterBoundary($"exit code {exitCode}");
             // An exit code means the executor just wrote its end block and IME is about to
             // write the result — both land at a stale stream position when another process
             // appended meanwhile. Check the ledgers on the next pass.
@@ -465,17 +543,24 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         {
             var outputType = parameters != null && parameters.TryGetValue("outputType", out var ot) ? ot : null;
             var script = GetCurrentScriptForLineUpdate(parameters);
-            if (script == null) return;
+            if (script == null)
+            {
+                LogLineBehindWriterBoundary($"script output ({outputType ?? "combined"})");
+                return;
+            }
 
             // PS-AGENT-OUTPUT captures both stdout and stderr in one pattern
             var output = match.Groups["output"]?.Value;
-            var error = match.Groups["error"]?.Value;
+            var error = match.Groups["error"];
 
-            if (!string.IsNullOrEmpty(output) && !string.IsNullOrEmpty(error))
+            if (error != null && error.Success)
             {
-                // Combined pattern (write output done. output = ..., error = ...)
-                script.Stdout = TruncateOutput(output.Trim());
-                script.Stderr = TruncateOutput(error.Trim());
+                // Combined pattern (write output done. output = ..., error = ...): both texts as
+                // AgentExecutor wrote them to the result files — the error part is the error file
+                // IME judges. The "error from script" line before it is a snapshot taken before the
+                // output readers finished, so this one replaces it, an empty stdout included.
+                script.Stdout = TruncateOutput(output?.Trim());
+                script.Stderr = TruncateOutput(error.Value.Trim());
             }
             else if (string.Equals(outputType, "stderr", StringComparison.OrdinalIgnoreCase))
             {
@@ -507,7 +592,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
 
             if (string.IsNullOrEmpty(id)) return;
 
-            CompletePlatformScriptFromImeResult(id, result, LastMatchedLogTimestamp, LastMatchedPatternId, CaptureLastMatchedProvenance());
+            CompletePlatformScriptFromImeResult(id, result, LastMatchedLogTimestamp, LastMatchedPatternId, CaptureLastMatchedProvenance(), ImeUserIdFrom(match.Value));
         }
 
         /// <summary>
@@ -521,48 +606,46 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         /// line reopened the slot, produced a fallback duplicate (session e7f3c910).
         /// <see cref="FlushPendingPlatformScriptResults"/> emits the held completion.
         /// </summary>
-        internal void CompletePlatformScriptFromImeResult(string policyId, string result, DateTime? resultLineTimestampUtc, string patternId, CmTraceLineProvenance resultProvenance)
+        internal void CompletePlatformScriptFromImeResult(string policyId, string result, DateTime? resultLineTimestampUtc, string patternId, CmTraceLineProvenance resultProvenance, string userId = null)
         {
-            // Dedup: the deadline-based fallback (FlushPendingPlatformScriptResults) may already have
-            // emitted this script from its AgentExecutor exit code because IME's authoritative
-            // PS-SCRIPT-RESULT line arrived late. The fallback carries the same exit code + stdout,
-            // so re-emitting here would duplicate the timeline entry and inflate counts. Drop the
-            // now-redundant pending entry and skip.
-            if (_platformScriptResultEmitted.ContainsKey(policyId))
+            // The result belongs to the run of this policy that started last before its line —
+            // the run in flight, or an earlier one that waits for its result while a later run
+            // already started (ParkPlatformRun).
+            var script = FindRunForResult(policyId, userId, resultLineTimestampUtc);
+            if (script == null)
             {
-                _logger.Debug($"ImeLogTracker: platform script {policyId} PS-SCRIPT-RESULT arrived after fallback emit — skipping duplicate");
-                _pendingPlatformScripts.Remove(policyId);
-                return;
-            }
+                // Dedup: the deadline-based fallback (FlushPendingPlatformScriptResults) may already
+                // have emitted this run from its AgentExecutor end block because IME's authoritative
+                // PS-SCRIPT-RESULT line arrived late, or the same result line is read again.
+                // Re-emitting would duplicate the timeline entry and inflate counts.
+                if (_platformScriptResultEmitted.ContainsKey(policyId))
+                {
+                    _logger.Debug($"ImeLogTracker: platform script {policyId} PS-SCRIPT-RESULT arrived after its run was emitted — skipping duplicate");
+                    return;
+                }
 
-            // Merge with pending AgentExecutor data if available
-            if (_pendingPlatformScripts.TryGetValue(policyId, out var script))
-            {
-                // Stale-result guard: on an intra-lifetime re-run of the same policy, run 1's
-                // late PS-SCRIPT-RESULT can arrive after run 2's start line already created a
-                // fresh slot (the start clears the emitted-marker). Merging would pair run 2's
-                // StartedAtUtc/state with run 1's result and then drop run 2's genuine result at
-                // the marker check above. A result line always postdates its own run's start
-                // line in the source log, so a result older than the pending slot's start
-                // belongs to a previous run — drop it and keep the live slot intact.
-                if (script.StartedAtUtc.HasValue
-                    && resultLineTimestampUtc.HasValue
-                    && resultLineTimestampUtc.Value < script.StartedAtUtc.Value)
+                // Stale-result guard: every run of this policy in flight started after the result
+                // line — a result line always postdates its own run's start line in the source log,
+                // so it belongs to a previous run. Keep the live runs intact.
+                if (HasLivePlatformRun(policyId))
                 {
                     _logger.Debug($"ImeLogTracker: platform script {policyId} result predates the current run's start — stale result from a previous run, skipping");
                     return;
                 }
-            }
-            else
-            {
+
                 script = new ScriptExecutionState
                 {
                     PolicyId = policyId,
-                    ScriptType = "platform"
+                    ScriptType = "platform",
+                    UserId = userId,
+                    RunId = NewRunId(),
                 };
                 _pendingPlatformScripts[policyId] = script;
+                ScriptRuns.NoteStarted(userId, policyId, UtcNowProvider());
             }
 
+            if (script.UserId == null && userId != null) script.UserId = userId;
+            ResolveParkedRunsBefore(script);
             script.Result = result;
             script.ResultSource = "ime_policy_result";
             script.ResultObservedAtUtc = resultLineTimestampUtc ?? UtcNowProvider();
@@ -591,19 +674,150 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         private void EmitPlatformScriptResult(ScriptExecutionState script, string note = null)
         {
             _logger.Info($"ImeLogTracker: platform script completed: {script.PolicyId}, result={script.Result}, exit={script.ExitCode}{(note != null ? $" ({note})" : string.Empty)}");
+            if (string.IsNullOrEmpty(script.RunId)) script.RunId = NewRunId();
             EmitScriptEvent(script);
+            // The register keeps the latest run per (user, policy) for the registry reconciliation:
+            // a run that waited for its result while a later one started must not take that later
+            // run's entry.
+            if (!HasLaterLivePlatformRun(script)) ScriptRuns.NoteEmitted(script, UtcNowProvider());
             // The run's source stamp, capped at the clock: a result line cannot be read before it
             // was written, so a stamp ahead of the clock is a wrong zone assumption on that line
             // (a rewound result resolved in the reader's zone, session 4377911b: +1 h). Left
             // uncapped, the marker made the genuine NEXT run's start line read as a late line of
-            // this run and its result a duplicate.
+            // this run and its result a duplicate. Only ever raised: a run emitted after a later
+            // one must not move the reference back.
             var runStamp = script.ResultObservedAtUtc ?? script.ExitObservedAtUtc ?? UtcNowProvider();
             var nowUtc = UtcNowProvider();
-            _platformScriptResultEmitted[script.PolicyId] = runStamp > nowUtc ? nowUtc : runStamp;
-            _pendingPlatformScripts.Remove(script.PolicyId);
+            var stamp = runStamp > nowUtc ? nowUtc : runStamp;
+            if (!_platformScriptResultEmitted.TryGetValue(script.PolicyId, out var previousStamp) || stamp > previousStamp)
+                _platformScriptResultEmitted[script.PolicyId] = stamp;
+            if (_pendingPlatformScripts.TryGetValue(script.PolicyId, out var current) && ReferenceEquals(current, script))
+                _pendingPlatformScripts.Remove(script.PolicyId);
+            else
+                _parkedPlatformScripts.Remove(script);
             _stateDirty = true;
         }
 
+        private static string NewRunId() => Guid.NewGuid().ToString("D");
+
+        /// <summary>A run older than this by source time is from a previous enrollment, not a run in flight.</summary>
+        private static readonly TimeSpan StalePlatformRunAge = TimeSpan.FromHours(24);
+
+        private static bool SameUserOrUnknown(string a, string b)
+            => a == null || b == null || string.Equals(a, b, StringComparison.OrdinalIgnoreCase);
+
+        private static DateTime StartOf(ScriptExecutionState run) => run.StartedAtUtc ?? DateTime.MinValue;
+
+        /// <summary>The runs of a policy that are not emitted yet: the earlier ones waiting for their IME result, then the one in flight.</summary>
+        private IEnumerable<ScriptExecutionState> LivePlatformRuns(string policyId)
+        {
+            foreach (var run in _parkedPlatformScripts)
+            {
+                if (string.Equals(run.PolicyId, policyId, StringComparison.OrdinalIgnoreCase)) yield return run;
+            }
+            if (_pendingPlatformScripts.TryGetValue(policyId, out var current)) yield return current;
+        }
+
+        private bool HasLivePlatformRun(string policyId) => LivePlatformRuns(policyId).Any();
+
+        /// <summary>The live run a start marker names, or null once that run was emitted.</summary>
+        private ScriptExecutionState FindLivePlatformRun(string policyId, string runId)
+            => LivePlatformRuns(policyId).FirstOrDefault(r => string.Equals(r.RunId, runId, StringComparison.Ordinal));
+
+        private bool HasLaterLivePlatformRun(ScriptExecutionState script)
+            => LivePlatformRuns(script.PolicyId).Any(r => !ReferenceEquals(r, script)
+                && SameUserOrUnknown(r.UserId, script.UserId) && StartOf(r) > StartOf(script));
+
+        /// <summary>
+        /// The live run an IME result line belongs to: of the runs of its policy that started at or before the line,
+        /// the latest — one of the same IME user when there is one.
+        /// </summary>
+        private ScriptExecutionState FindRunForResult(string policyId, string userId, DateTime? resultLineTimestampUtc)
+        {
+            ScriptExecutionState sameUser = null, anyUser = null;
+            foreach (var run in LivePlatformRuns(policyId))
+            {
+                if (resultLineTimestampUtc.HasValue && run.StartedAtUtc.HasValue && run.StartedAtUtc.Value > resultLineTimestampUtc.Value) continue;
+                if (anyUser == null || StartOf(run) > StartOf(anyUser)) anyUser = run;
+                if (SameUserOrUnknown(run.UserId, userId) && (sameUser == null || StartOf(run) > StartOf(sameUser))) sameUser = run;
+            }
+            return sameUser ?? anyUser;
+        }
+
+        /// <summary>
+        /// Moves the run in flight aside when the next executor run of its policy starts: it keeps its own end block and
+        /// waits for its IME result (<see cref="FindRunForResult"/>), the exit-code fallback, or a later run's result.
+        /// </summary>
+        private void ParkPlatformRun(ScriptExecutionState run)
+        {
+            _pendingPlatformScripts.Remove(run.PolicyId);
+            _parkedPlatformScripts.Add(run);
+            _stateDirty = true;
+            if (_parkedPlatformScripts.Count > MaxParkedPlatformScripts)
+            {
+                var oldest = _parkedPlatformScripts.OrderBy(StartOf).First();
+                _logger.Warning($"ImeLogTracker: more than {MaxParkedPlatformScripts} platform runs wait for their IME result — resolving the oldest ({oldest.PolicyId}, started {oldest.StartedAtUtc:o}) now");
+                ResolveParkedRun(oldest, "too many runs waiting for their IME result");
+            }
+            _logger.Debug($"ImeLogTracker: platform script {run.PolicyId}: the next executor run started before IME's result of run {run.RunId} was read — that run keeps its end block and waits for its result");
+        }
+
+        /// <summary>
+        /// Results arrive in run order: a parked run of the same IME user that started before the run a result belongs to
+        /// gets none any more (its result line was lost) — it goes out now, ahead of the later run.
+        /// </summary>
+        private void ResolveParkedRunsBefore(ScriptExecutionState owner)
+        {
+            if (_parkedPlatformScripts.Count == 0 || !owner.StartedAtUtc.HasValue) return;
+            var earlier = _parkedPlatformScripts
+                .Where(r => !ReferenceEquals(r, owner)
+                    && string.Equals(r.PolicyId, owner.PolicyId, StringComparison.OrdinalIgnoreCase)
+                    && SameUserOrUnknown(r.UserId, owner.UserId)
+                    && r.StartedAtUtc.HasValue && r.StartedAtUtc.Value < owner.StartedAtUtc.Value)
+                .OrderBy(StartOf)
+                .ToList();
+            foreach (var run in earlier) ResolveParkedRun(run, "a later run of this policy got its IME result first");
+        }
+
+        /// <summary>A parked run that will not get its IME result: out with what it has, or dropped when it has nothing.</summary>
+        private void ResolveParkedRun(ScriptExecutionState run, string why)
+        {
+            if (run.Result != null)
+            {
+                EmitPlatformScriptResult(run, why);
+            }
+            else if (run.ExitCode.HasValue)
+            {
+                EmitFromExecutorEndBlock(run, why);
+            }
+            else
+            {
+                _parkedPlatformScripts.Remove(run);
+                _stateDirty = true;
+                _logger.Debug($"ImeLogTracker: platform script {run.PolicyId} run {run.RunId} has neither IME result nor executor end block — dropped ({why})");
+            }
+        }
+
+        /// <summary>
+        /// IME's own verdict from a run's end block: Success exactly when the error file was empty
+        /// (<c>IsNullOrEmpty(errorFile.Trim())</c> in IME), whatever the exit code — PowerShell returns 0 after a
+        /// non-terminating error and any code a script exits with. Only when the stderr line was never read does the
+        /// exit code stand in.
+        /// </summary>
+        internal static string ImeResultFromEndBlock(ScriptExecutionState script)
+        {
+            if (script.Stderr != null) return string.IsNullOrWhiteSpace(script.Stderr) ? "Success" : "Failed";
+            return script.ExitCode == 0 ? "Success" : "Failed";
+        }
+
+        private void EmitFromExecutorEndBlock(ScriptExecutionState script, string why)
+        {
+            script.Result = ImeResultFromEndBlock(script);
+            script.ResultSource = "agentexecutor_fallback";
+            var basis = script.Stderr == null ? $"exit code {script.ExitCode}, stderr not read" : script.Stderr.Trim().Length == 0 ? "empty stderr" : "stderr present";
+            EmitPlatformScriptResult(script, $"{why} — {script.Result} from the executor end block ({basis}) (fallback)");
+        }
+
         /// <summary>
         /// Grace period after a platform script's AgentExecutor exit code is observed before
         /// <see cref="FlushPendingPlatformScriptResults"/> emits a completion from that exit code.
@@ -641,29 +855,48 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         /// out once its executor end block has been read — the block arrives within one pass, so
         /// stdout/stderr are in by now — or after <see cref="PlatformScriptEndBlockGrace"/>.</item>
         /// <item>A script with a known AgentExecutor exit code but no IME <c>PS-SCRIPT-RESULT</c>
-        /// line within <see cref="PlatformScriptResultGrace"/> is emitted from the exit code
-        /// (0 → Success, else Failed), tagged <c>resultSource=agentexecutor_fallback</c> so the
-        /// data is honest about its provenance. Without this, scripts that completed shortly
-        /// before the agent terminates were silently dropped.</item>
+        /// line within <see cref="PlatformScriptResultGrace"/> is emitted from its end block by
+        /// IME's own rule (<see cref="ImeResultFromEndBlock"/>), tagged
+        /// <c>resultSource=agentexecutor_fallback</c> so the data is honest about its provenance.
+        /// Without this, scripts that completed shortly before the agent terminates were silently
+        /// dropped.</item>
         /// </list>
+        /// Parked runs go first, oldest first, so a policy's runs leave in run order; one without
+        /// result and end block keeps waiting — across a shutdown too — until a later run's result
+        /// resolves it or it is a day old.
         /// Runs on the single-threaded polling loop (no locking needed, same as the handlers).
         /// <paramref name="force"/> bypasses both grace checks for the final pass on shutdown.
         /// </summary>
         internal void FlushPendingPlatformScriptResults(DateTime nowUtc, bool force = false)
         {
-            if (_pendingPlatformScripts.Count == 0) return;
+            if (_pendingPlatformScripts.Count == 0 && _parkedPlatformScripts.Count == 0) return;
 
             var fallbackEmitted = false;
-            foreach (var script in _pendingPlatformScripts.Values.ToList())
+            foreach (var run in _parkedPlatformScripts.OrderBy(StartOf).ToList())
             {
-                // Already emitted by the authoritative path — just drop the stale buffer entry.
-                if (_platformScriptResultEmitted.ContainsKey(script.PolicyId))
+                if (run.Result != null)
                 {
-                    _pendingPlatformScripts.Remove(script.PolicyId);
-                    _stateDirty = true;
+                    if (run.ExitCode.HasValue || force || !run.ResultHeldSinceUtc.HasValue || nowUtc - run.ResultHeldSinceUtc.Value >= PlatformScriptEndBlockGrace)
+                        EmitPlatformScriptResult(run, run.ExitCode.HasValue ? "executor end block read after the result" : $"no executor end block within {PlatformScriptEndBlockGrace.TotalSeconds:F0}s");
                     continue;
                 }
+                if (run.ExitCode.HasValue)
+                {
+                    if (!force && (!run.ExitObservedAtUtc.HasValue || nowUtc - run.ExitObservedAtUtc.Value < PlatformScriptResultGrace)) continue;
+                    EmitFromExecutorEndBlock(run, $"result not seen within {PlatformScriptResultGrace.TotalSeconds:F0}s{(force ? ", shutdown flush" : string.Empty)}");
+                    fallbackEmitted = true;
+                    continue;
+                }
+                if (run.StartedAtUtc.HasValue && nowUtc - run.StartedAtUtc.Value > StalePlatformRunAge)
+                {
+                    _parkedPlatformScripts.Remove(run);
+                    _stateDirty = true;
+                    _logger.Debug($"ImeLogTracker: platform script {run.PolicyId} run {run.RunId} waited a day without IME result or executor end block — dropped");
+                }
+            }
 
+            foreach (var script in _pendingPlatformScripts.Values.ToList())
+            {
                 if (script.Result != null)
                 {
                     if (script.ExitCode.HasValue)
@@ -682,10 +915,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                     if (nowUtc - script.ExitObservedAtUtc.Value < PlatformScriptResultGrace) continue;
                 }
 
-                script.Result = script.ExitCode.Value == 0 ? "Success" : "Failed";
-                script.ResultSource = "agentexecutor_fallback";
-                EmitPlatformScriptResult(script,
-                    $"result not seen within {PlatformScriptResultGrace.TotalSeconds:F0}s{(force ? ", shutdown flush" : string.Empty)} — emitted from AgentExecutor exit code {script.ExitCode.Value} (fallback)");
+                EmitFromExecutorEndBlock(script, $"result not seen within {PlatformScriptResultGrace.TotalSeconds:F0}s{(force ? ", shutdown flush" : string.Empty)}");
                 fallbackEmitted = true;
             }
 
@@ -697,7 +927,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         /// <summary>Test seam: inject a pending platform script as if AgentExecutor.log had reported
         /// its start + exit code, without an IME PS-SCRIPT-RESULT line.</summary>
         internal void SeedPendingPlatformScriptForTesting(string policyId, int? exitCode, DateTime? exitObservedAtUtc, string stdout = null, DateTime? startedAtUtc = null,
-            CmTraceLineProvenance startedAtProvenance = null, CmTraceLineProvenance exitProvenance = null)
+            CmTraceLineProvenance startedAtProvenance = null, CmTraceLineProvenance exitProvenance = null, string stderr = null)
         {
             // Mirrors a fresh execution start: a new run clears any prior emitted-marker (see
             // HandleScriptStarted) so re-runs of the same policy within one lifetime emit again.
@@ -706,9 +936,11 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             {
                 PolicyId = policyId,
                 ScriptType = "platform",
+                RunId = NewRunId(),
                 ExitCode = exitCode,
                 ExitObservedAtUtc = exitObservedAtUtc,
                 Stdout = stdout,
+                Stderr = stderr,
                 StartedAtUtc = startedAtUtc,
                 StartedAtProvenance = startedAtProvenance,
                 ExitProvenance = exitProvenance,
@@ -717,6 +949,9 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             RecordInvocationMarker(policyId, isClose: false);
         }
 
+        /// <summary>Test seam: earlier runs waiting for their IME result while a later run of their policy is in flight.</summary>
+        internal int ParkedPlatformScriptCountForTest => _parkedPlatformScripts.Count;
+
         /// <summary>Test seam: the authoritative IME PS-SCRIPT-RESULT path for a platform script
         /// (the production handler minus regex extraction). <paramref name="resultLineTimestampUtc"/>
         /// stands in for the CMTrace timestamp of the PS-SCRIPT-RESULT line (production reads it
@@ -1163,11 +1398,11 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         internal static readonly TimeSpan HeldScriptStartGrace = TimeSpan.FromMinutes(30);
         internal static readonly TimeSpan HeldScriptStartShutdownGrace = TimeSpan.FromMinutes(5);
 
-        private static string TruncateOutput(string output)
+        internal static string TruncateOutput(string output)
         {
             if (string.IsNullOrEmpty(output) || output.Length <= MaxScriptOutputLength)
                 return output;
-            return output.Substring(0, MaxScriptOutputLength) + "...[truncated]";
+            return output.Substring(0, MaxScriptOutputLength) + OutputTruncationMarker;
         }
 
         // -----------------------------------------------------------------------

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/Ime/ImeLogTracker.LogProcessing.cs

@@ -123,16 +123,19 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             var ledger = IsMultiWriterLogFile(fileName) ? GetLedger(fileName) : null;
 
             // Set by a rewind: entries that still read unchanged behind the old bookmark are
-            // skipped, and nothing below the old bookmark is fresh or a calibration anchor.
-            HashSet<LedgerEntry> rewoundEntries = null;
+            // skipped (their invocation markers are given back); a changed entry below the old
+            // bookmark is fresh only when the bytes it replaced were seen moments ago, and never a
+            // calibration anchor.
+            RewindState rewind = null;
             long oldBookmark = -1;
+            var writerBoundaries = IsWriterBoundaryLogFile(fileName);
 
             if (ledger != null)
             {
                 var rewindTo = await PrepareLedgerAsync(filePath, fileName, ledger, startPos, passNowUtc, token);
                 if (rewindTo >= 0)
                 {
-                    rewoundEntries = ApplyRewind(filePath, fileName, ledger, rewindTo, startPos);
+                    rewind = ApplyRewind(filePath, fileName, ledger, rewindTo, startPos);
                     oldBookmark = startPos;
                     startPos = rewindTo;
                 }
@@ -164,21 +167,21 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             {
                 // Guard zone: the file grew and is open anyway — re-check the entries just behind
                 // the bookmark, where a stale writer's block lands when it is short.
-                if (ledger != null && rewoundEntries == null && ledger.Entries.Count > 0)
+                if (ledger != null && rewind == null && ledger.Entries.Count > 0)
                 {
                     var guardFrom = ledger.OffsetOfEntryAtOrAfter(startPos - OverwriteGuardBytes);
                     if (guardFrom >= 0 && guardFrom < startPos)
                     {
-                        var divergence = await FindOverwriteAsync(stream, ledger, guardFrom, startPos, token);
+                        var divergence = await FindOverwriteAsync(stream, ledger, guardFrom, startPos, passNowUtc, token);
                         _verifiedBytes += startPos - guardFrom;
                         if (divergence >= 0)
                         {
                             // The guard saw only the tail of the ledger; the block may start earlier.
-                            var earliest = await FindOverwriteAsync(stream, ledger, ledger.StartOffset, startPos, token);
+                            var earliest = await FindOverwriteAsync(stream, ledger, ledger.StartOffset, startPos, passNowUtc, token);
                             _verifiedBytes += startPos - ledger.StartOffset;
                             _verifyPasses++;
                             if (earliest >= 0) divergence = earliest;
-                            rewoundEntries = ApplyRewind(filePath, fileName, ledger, divergence, startPos);
+                            rewind = ApplyRewind(filePath, fileName, ledger, divergence, startPos);
                             oldBookmark = startPos;
                             startPos = divergence;
                         }
@@ -259,7 +262,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                         // A fragment right at the bookmark of a multi-writer file (the previous
                         // entry ended exactly here, this one does not open an entry) is the tail of
                         // a block a stale writer laid over already-read bytes: verify before reading on.
-                        if (ledger != null && rewoundEntries == null && entry.Offset == ledger.EndOffset
+                        if (ledger != null && rewind == null && entry.Offset == ledger.EndOffset
                             && ledger.LastFragmentOffset != entry.Offset && !entry.Text.StartsWith("<![LOG["))
                         {
                             ledger.VerifyRequested = true;
@@ -269,11 +272,27 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                         }
                     }
 
-                    if (ledger != null) ledger.Record(entry);
-                    if (rewoundEntries != null && rewoundEntries.Contains(new LedgerEntry { Offset = entry.Offset, Hash = entry.Hash }))
-                        continue; // unchanged behind the old bookmark — processed before the rewind
+                    if (ledger != null) ledger.Record(entry, passNowUtc);
+                    var unchanged = rewind != null && rewind.IsUnchanged(entry);
+                    if (unchanged) RestoreInvocationMarkers(rewind, entry.Offset);
 
-                    _currentPassLinesAreFresh = passLinesAreFresh && entry.Offset >= oldBookmark;
+                    // Writer boundary (see ImeLogTracker.Overwrite.cs): an AgentExecutor.log entry that is
+                    // not exactly one CMTrace record ends the bytes of the executor in front of it. Never
+                    // matched — its text is the cut of two writers. Evaluated for unchanged entries too:
+                    // what owns the position in front of them may have changed with the rewind.
+                    if (writerBoundaries && !IsSingleCmTraceRecord(entry.Text))
+                    {
+                        CloseAtWriterBoundary(fileName, entry.Offset, entry.Text);
+                        continue;
+                    }
+
+                    if (unchanged) continue; // unchanged behind the old bookmark — processed before the rewind
+
+                    // Behind the old bookmark only changed entries arrive here: fresh when the bytes they replaced
+                    // were seen moments ago (RewoundEntryIsFresh), never a calibration anchor.
+                    _currentPassLinesAreFresh = entry.Offset >= oldBookmark
+                        ? passLinesAreFresh
+                        : rewind != null && RewoundEntryIsFresh(passLinesAreFresh, rewind.EntryAtRewindPointReplaced, rewind.OldestReplacedSeenUtc, passNowUtc);
 
                     // --- Normal processing (single-line or completed multiline) ---
                     CmTraceLogEntry parsed;

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/Ime/ImeLogTracker.Overwrite.cs

@@ -62,6 +62,11 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             public long Offset;
             public int Length;
             public ulong Hash;
+            /// <summary>
+            /// When these bytes were last seen as they are (read, seeded or verified unchanged): bytes found different
+            /// at this position later were written after it. Not part of the identity.
+            /// </summary>
+            public DateTime SeenUtc;
 
             // Identity is (offset, hash): a tail first read unterminated and later completed
             // keeps its hash but grows by its terminator.
@@ -100,11 +105,11 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                 return idx < Entries.Count ? Entries[idx].Offset : -1;
             }
 
-            public void Record(AssembledEntry e)
+            public void Record(AssembledEntry e, DateTime seenUtc)
             {
                 var idx = IndexOfFirstAtOrAfter(e.Offset);
                 if (idx < Entries.Count) Entries.RemoveRange(idx, Entries.Count - idx);
-                Entries.Add(new LedgerEntry { Offset = e.Offset, Length = e.Length, Hash = e.Hash });
+                Entries.Add(new LedgerEntry { Offset = e.Offset, Length = e.Length, Hash = e.Hash, SeenUtc = seenUtc });
             }
 
             /// <summary>Drops everything from <paramref name="offset"/> on and returns it — the entries a rewind must not process twice.</summary>
@@ -197,7 +202,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             {
                 ledger.Seeded = true;
                 if (ledger.Entries.Count == 0 && bookmark > 0)
-                    await SeedLedgerAsync(filePath, ledger, bookmark, token).ConfigureAwait(false);
+                    await SeedLedgerAsync(filePath, ledger, bookmark, nowUtc, token).ConfigureAwait(false);
             }
 
             var due = ledger.VerifyRequested || (InContention(nowUtc) && nowUtc >= ledger.NextCadenceVerifyUtc);
@@ -213,7 +218,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
 
             long divergence;
             using (var stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
-                divergence = await FindOverwriteAsync(stream, ledger, from, bookmark, token).ConfigureAwait(false);
+                divergence = await FindOverwriteAsync(stream, ledger, from, bookmark, nowUtc, token).ConfigureAwait(false);
             if (token.IsCancellationRequested) return -1;
 
             ledger.VerifyRequested = false;
@@ -228,8 +233,9 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         /// Re-reads [fromOffset, toOffset) with the read loop's assembler and compares against the
         /// ledger. Returns the offset of the first entry whose bytes changed — a ledger entry not
         /// reproduced, or an entry the ledger never had — or -1 when everything reads as before.
+        /// Every entry found unchanged is stamped seen at <paramref name="nowUtc"/>.
         /// </summary>
-        private async Task<long> FindOverwriteAsync(FileStream stream, FileLedger ledger, long fromOffset, long toOffset, CancellationToken token)
+        private async Task<long> FindOverwriteAsync(FileStream stream, FileLedger ledger, long fromOffset, long toOffset, DateTime nowUtc, CancellationToken token)
         {
             var entries = ledger.Entries;
             var idx = ledger.IndexOfFirstAtOrAfter(fromOffset);
@@ -255,6 +261,9 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                 if (idx < entries.Count && entries[idx].Offset == e.Offset)
                 {
                     if (entries[idx].Hash != e.Hash) return e.Offset;
+                    var confirmed = entries[idx];
+                    confirmed.SeenUtc = nowUtc;
+                    entries[idx] = confirmed;
                     idx++;
                     continue;
                 }
@@ -265,7 +274,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         }
 
         /// <summary>After a restart the ledger is empty: fingerprint the entries just behind the persisted bookmark without processing them.</summary>
-        private async Task SeedLedgerAsync(string filePath, FileLedger ledger, long bookmark, CancellationToken token)
+        private async Task SeedLedgerAsync(string filePath, FileLedger ledger, long bookmark, DateTime nowUtc, CancellationToken token)
         {
             var from = Math.Max(0, bookmark - RestartSeedBytes);
             using (var stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
@@ -288,18 +297,69 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                     if (assembler.Feed(line, reader.LastLineStart, reader.Position, reader.LastLineTruncated, reader.LastLineHash, out e)
                             == CmTraceEntryAssembler.Outcome.Entry
                         && e.Offset + e.Length <= bookmark)
-                        ledger.Record(e);
+                        ledger.Record(e, nowUtc);
                 }
             }
         }
 
-        /// <summary>Moves the bookmark back to the first changed entry; returns the entries to skip if they still read unchanged behind it.</summary>
-        private HashSet<LedgerEntry> ApplyRewind(string filePath, string fileName, FileLedger ledger, long rewindTo, long bookmark)
+        /// <summary>
+        /// What one rewind pass carries: the entries to skip if they still read unchanged behind the rewind point, and
+        /// the invocation markers set aside there until their entries prove unchanged. Pass-local by design — whatever
+        /// is not given back dies with the pass on every exit path.
+        /// </summary>
+        private sealed class RewindState
+        {
+            public RewindState(string fileName, HashSet<LedgerEntry> unchanged, List<InvocationMarker> markers, InvocationMarker lastPlatformMarker, long rewindTo)
+            {
+                FileName = fileName;
+                Unchanged = unchanged;
+                Markers = markers;
+                LastPlatformMarker = lastPlatformMarker;
+                foreach (var replaced in unchanged)
+                {
+                    if (replaced.Offset == rewindTo) EntryAtRewindPointReplaced = true;
+                    if (!OldestReplacedSeenUtc.HasValue || replaced.SeenUtc < OldestReplacedSeenUtc.Value) OldestReplacedSeenUtc = replaced.SeenUtc;
+                }
+            }
+
+            public string FileName { get; }
+            public HashSet<LedgerEntry> Unchanged { get; }
+            /// <summary>Set aside at the rewind, ascending by offset.</summary>
+            public List<InvocationMarker> Markers { get; }
+            /// <summary>The tracker-wide last platform marker, when it was among the set-aside ones.</summary>
+            public InvocationMarker LastPlatformMarker { get; }
+            public int Next { get; set; }
+            /// <summary>The ledger held the entry at the rewind point: the changed bytes lie where something was seen before.</summary>
+            public bool EntryAtRewindPointReplaced { get; }
+            /// <summary>The earliest time any of the replaced bytes was last seen as it was: every changed byte was written after it.</summary>
+            public DateTime? OldestReplacedSeenUtc { get; }
+
+            public bool IsUnchanged(AssembledEntry entry) => Unchanged.Contains(new LedgerEntry { Offset = entry.Offset, Hash = entry.Hash });
+        }
+
+        /// <summary>
+        /// Whether an entry a rewind re-processes (it reads differently than before) is fresh. Its bytes were written after
+        /// the bytes it replaced were last seen as they were — IME stamps a line when it writes it — so when that was at
+        /// most <see cref="FreshLineMaxAge"/> ago the entry's age is bounded like an appended line's and it may anchor
+        /// itself (session d29e27e3: recovered result lines fell back to the agent's stale zone and lost their duration).
+        /// Not fresh when the pass is not (the first pass after a restart never anchors), when the divergence lies in bytes
+        /// the ledger never held (nothing dates them), or when the clock stepped back since.
+        /// </summary>
+        internal static bool RewoundEntryIsFresh(bool passLinesAreFresh, bool entryAtRewindPointReplaced, DateTime? oldestReplacedSeenUtc, DateTime passNowUtc)
+        {
+            if (!passLinesAreFresh || !entryAtRewindPointReplaced || !oldestReplacedSeenUtc.HasValue) return false;
+            var sinceSeen = passNowUtc - oldestReplacedSeenUtc.Value;
+            return sinceSeen >= TimeSpan.Zero && sinceSeen <= FreshLineMaxAge;
+        }
+
+        /// <summary>Moves the bookmark back to the first changed entry; returns what the re-read needs to skip and to give back.</summary>
+        private RewindState ApplyRewind(string filePath, string fileName, FileLedger ledger, long rewindTo, long bookmark)
         {
             var removed = ledger.TruncateFrom(rewindTo);
             _positionTracker.SetPosition(filePath, rewindTo);
             _heldTails.Remove(filePath);
-            InvalidateInvocationMarkersFrom(fileName, rewindTo);
+            var lastPlatformMarker = _lastPlatformMarker;
+            var markers = TakeInvocationMarkersFrom(fileName, rewindTo, out var tookLastPlatformMarker);
             _overwriteRewinds++;
             _overwriteBytesReprocessed += bookmark - rewindTo;
 
@@ -314,7 +374,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             {
                 _logger.Debug(message);
             }
-            return removed;
+            return new RewindState(fileName, removed, markers, tookLastPlatformMarker ? lastPlatformMarker : null, rewindTo);
         }
 
         private long RetentionFloor(string fileName, long bookmark)
@@ -331,20 +391,44 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         // -----------------------------------------------------------------------
         //
         // AgentExecutor.log carries "Powershell exit code is N" / "write output done" without a
-        // policy id. Their owner is decided by FILE POSITION, not by the order lines were read:
-        // an executor writes its end block at its own stream position, i.e. directly after its
-        // own start block in the final bytes, so the nearest preceding invocation marker names
-        // it — and stays right after a rewind re-reads that region. A marker is a platform start
-        // (policy id), some other invocation (detection, remediation, requirement: null) or a
-        // close ("gets invoked" banner, "Agent executor completed").
+        // policy id. Their owner is decided by FILE POSITION: the nearest preceding marker — a
+        // platform start (policy id), some other invocation (detection, remediation, requirement:
+        // null), a close ("gets invoked" banner, "Agent executor completed") or a writer boundary.
+        //
+        // Every executor writes its lines contiguously from its own stream position, so its end
+        // block follows its own start block — but that start block may be gone. Two executors that
+        // open the file at the same end write their start blocks over each other, and the end block
+        // of the one that lost then sits behind the OTHER executor's start block (session 756970cf:
+        // a detection script's exit code and output on a platform script). Where one writer's bytes
+        // meet another's, the cut leaves an entry that is not exactly one CMTrace record — a
+        // fragment, a merged line or an empty line — unless the line boundaries of both writers
+        // coincide byte-exactly. That writer boundary closes the platform invocation in front of it.
+        // AgentExecutor.log only: in the IME log the service writes the markers and the lines they
+        // own itself, and its fragments are executor telemetry lines.
+        //
+        // A marker lives exactly as long as the bytes of its entry: a rewind sets the markers from
+        // the rewind point on aside, and an entry that reads unchanged gets its markers back.
 
         private sealed class InvocationMarker
         {
             public long Offset;
             public string PolicyId;
+            /// <summary>
+            /// The platform run the start line belongs to: the lines behind it go to that run while it is pending or
+            /// waits for its IME result, and nowhere once it was emitted — never to a later run of the same policy.
+            /// Null only on seeded test markers, which resolve by policy.
+            /// </summary>
+            public string RunId;
             public bool IsClose;
+            /// <summary>Set on a writer boundary: the platform invocation it closed.</summary>
+            public string ClosedPolicyId;
         }
 
+        /// <summary>Run id of a start line whose run was emitted already (a late line): owns its lines, matches no live run.</summary>
+        private const string EmittedRunId = "emitted";
+
+        private const string ExecutorLogFileName = "AgentExecutor.log";
+
         private readonly Dictionary<string, List<InvocationMarker>> _invocationMarkers =
             new Dictionary<string, List<InvocationMarker>>(StringComparer.OrdinalIgnoreCase);
         private InvocationMarker _lastPlatformMarker;
@@ -354,24 +438,62 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         private readonly HashSet<string> _platformMarkerFiles = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
         private long _testEntryOrdinal;
 
-        private void RecordInvocationMarker(string policyId, bool isClose)
+        /// <summary>
+        /// The executor log, live or rotated (<c>AgentExecutor-yyyyMMdd-HHmmss.log</c>): its invocations are one process
+        /// each, so a writer boundary ends an invocation — in the final bytes of a rotation as much as in the live file.
+        /// </summary>
+        internal static bool IsWriterBoundaryLogFile(string fileName)
+            => string.Equals(fileName, ExecutorLogFileName, StringComparison.OrdinalIgnoreCase)
+            || (fileName != null
+                && fileName.StartsWith("AgentExecutor-", StringComparison.OrdinalIgnoreCase)
+                && fileName.EndsWith(".log", StringComparison.OrdinalIgnoreCase));
+
+        /// <summary>
+        /// True when the entry is exactly one CMTrace record: it opens with <c>&lt;![LOG[</c> (culture-sensitive like
+        /// <c>CmTraceLogParser.TryParseLine</c>, so a BOM is ignorable) and holds no second one — the parser takes the
+        /// message up to the LAST trailer, so a line cut anywhere, its trailer included, would swallow the record
+        /// written over it. An empty entry is the terminator of a cut line. A script whose own output contains the
+        /// open tag loses that output line: the bytes cannot tell it from a merged line.
+        /// </summary>
+        internal static bool IsSingleCmTraceRecord(string text)
+        {
+            if (string.IsNullOrEmpty(text) || !text.StartsWith(LogOpenTag)) return false;
+            var first = text.IndexOf(LogOpenTag, StringComparison.Ordinal);
+            return first >= 0 && text.IndexOf(LogOpenTag, first + LogOpenTag.Length, StringComparison.Ordinal) < 0;
+        }
+
+        private List<InvocationMarker> GetOrCreateMarkerList(string file)
         {
-            if (_currentEntryOffset < 0) return;
-            var file = _currentSourceFileName ?? TestSourceFileName;
             List<InvocationMarker> list;
             if (!_invocationMarkers.TryGetValue(file, out list))
             {
                 list = new List<InvocationMarker>();
                 _invocationMarkers[file] = list;
             }
+            return list;
+        }
+
+        private static void AppendInvocationMarker(List<InvocationMarker> list, InvocationMarker marker)
+        {
+            if (list.Count >= MaxInvocationMarkersPerFile) list.RemoveAt(0);
+            list.Add(marker);
+        }
+
+        private void RecordInvocationMarker(string policyId, bool isClose, string runId = null)
+        {
+            if (_currentEntryOffset < 0) return;
+            var file = _currentSourceFileName ?? TestSourceFileName;
+            var list = GetOrCreateMarkerList(file);
 
             if (list.Count > 0 && list[list.Count - 1].Offset == _currentEntryOffset)
             {
                 // Two patterns on one line: the platform start outranks the generic argument line.
+                // A writer boundary is never upgraded.
                 var last = list[list.Count - 1];
-                if (!isClose && policyId != null)
+                if (!isClose && policyId != null && last.ClosedPolicyId == null)
                 {
                     last.PolicyId = policyId;
+                    last.RunId = runId;
                     last.IsClose = false;
                     _lastPlatformMarker = last;
                     _platformMarkerFiles.Add(file);
@@ -379,9 +501,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                 return;
             }
 
-            if (list.Count >= MaxInvocationMarkersPerFile) list.RemoveAt(0);
-            var marker = new InvocationMarker { Offset = _currentEntryOffset, PolicyId = policyId, IsClose = isClose };
-            list.Add(marker);
+            var marker = new InvocationMarker { Offset = _currentEntryOffset, PolicyId = policyId, RunId = runId, IsClose = isClose };
+            AppendInvocationMarker(list, marker);
             if (!isClose && policyId != null)
             {
                 _lastPlatformMarker = marker;
@@ -390,21 +511,34 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         }
 
         /// <summary>
-        /// The pending platform script that owns the entry being processed, or null.
-        /// <paramref name="ownerPolicyId"/> names the owning platform script even when its slot is
-        /// gone (completion already emitted); null when no platform invocation owns the entry.
+        /// An entry of <paramref name="fileName"/> at <paramref name="offset"/> that is not exactly one CMTrace record:
+        /// the bytes behind it were written by another process than the bytes in front of it. Closes the platform
+        /// invocation that owns the position; records nothing when none is open there (a cut multi-line output yields
+        /// one fragment per line). Idempotent at the same offset.
         /// </summary>
-        private ScriptExecutionState ResolvePlatformScriptForCurrentEntry(out string ownerPolicyId)
+        private void CloseAtWriterBoundary(string fileName, long offset, string text)
+        {
+            var owner = FindOwningMarker(fileName, offset);
+            if (owner == null || owner.IsClose || owner.PolicyId == null) return;
+
+            var list = GetOrCreateMarkerList(fileName);
+            if (list.Count > 0 && list[list.Count - 1].Offset >= offset) return;
+            AppendInvocationMarker(list, new InvocationMarker { Offset = offset, IsClose = true, ClosedPolicyId = owner.PolicyId });
+
+            var kind = string.IsNullOrEmpty(text) ? "empty line" : text.StartsWith(LogOpenTag) ? "merged line" : "fragment";
+            _logger.Debug($"ImeLogTracker: writer boundary in {fileName} at offset {offset} ({kind}, {text?.Length ?? 0} chars) closes platform script {owner.PolicyId} (opened at {owner.Offset}) — the bytes behind it belong to another executor");
+        }
+
+        /// <summary>The marker that owns <paramref name="offset"/> in <paramref name="file"/>, or null.</summary>
+        private InvocationMarker FindOwningMarker(string file, long offset)
         {
-            ownerPolicyId = null;
-            var file = _currentSourceFileName ?? TestSourceFileName;
             InvocationMarker marker = null;
             List<InvocationMarker> list = null;
-            if (_currentEntryOffset >= 0 && _invocationMarkers.TryGetValue(file, out list))
+            if (offset >= 0 && _invocationMarkers.TryGetValue(file, out list))
             {
                 for (var i = list.Count - 1; i >= 0; i--)
                 {
-                    if (list[i].Offset <= _currentEntryOffset)
+                    if (list[i].Offset <= offset)
                     {
                         marker = list[i];
                         break;
@@ -420,24 +554,52 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             // (session 24dc69d1: the health-script worker's exit line pre-filled a platform slot's
             // exit code, its launch line the slot's context).
             if (marker == null && (list == null || list.Count == 0) && _platformMarkerFiles.Contains(file)) marker = _lastPlatformMarker;
+            return marker;
+        }
+
+        /// <summary>
+        /// The pending platform script that owns the entry being processed, or null.
+        /// <paramref name="ownerPolicyId"/> names the owning platform script even when its slot is
+        /// gone (completion already emitted); null when no platform invocation owns the entry.
+        /// </summary>
+        private ScriptExecutionState ResolvePlatformScriptForCurrentEntry(out string ownerPolicyId)
+        {
+            ownerPolicyId = null;
+            var marker = FindOwningMarker(_currentSourceFileName ?? TestSourceFileName, _currentEntryOffset);
             if (marker == null || marker.IsClose || marker.PolicyId == null) return null;
 
             ownerPolicyId = marker.PolicyId;
+            if (marker.RunId != null) return FindLivePlatformRun(marker.PolicyId, marker.RunId);
             ScriptExecutionState state;
             return _pendingPlatformScripts.TryGetValue(marker.PolicyId, out state) ? state : null;
         }
 
-        private void InvalidateInvocationMarkersFrom(string fileName, long offset)
+        /// <summary>Debug trace for an executor line that a writer boundary kept away from a platform script.</summary>
+        private void LogLineBehindWriterBoundary(string what)
         {
+            var marker = FindOwningMarker(_currentSourceFileName ?? TestSourceFileName, _currentEntryOffset);
+            if (marker?.ClosedPolicyId == null) return;
+            _logger.Debug($"ImeLogTracker: {what} at offset {_currentEntryOffset} lies behind the writer boundary at {marker.Offset} that closed platform script {marker.ClosedPolicyId} — another executor's end block, not attributed");
+        }
+
+        /// <summary>Removes the markers from <paramref name="offset"/> on and returns them in offset order.</summary>
+        private List<InvocationMarker> TakeInvocationMarkersFrom(string fileName, long offset, out bool tookLastPlatformMarker)
+        {
+            tookLastPlatformMarker = false;
+            var taken = new List<InvocationMarker>();
             List<InvocationMarker> list;
-            if (!_invocationMarkers.TryGetValue(fileName, out list) || list.Count == 0) return;
-            var removedLast = false;
-            for (var i = list.Count - 1; i >= 0 && list[i].Offset >= offset; i--)
+            if (!_invocationMarkers.TryGetValue(fileName, out list) || list.Count == 0) return taken;
+
+            var from = list.Count;
+            while (from > 0 && list[from - 1].Offset >= offset) from--;
+            for (var i = from; i < list.Count; i++)
             {
-                if (ReferenceEquals(list[i], _lastPlatformMarker)) removedLast = true;
-                list.RemoveAt(i);
+                if (ReferenceEquals(list[i], _lastPlatformMarker)) tookLastPlatformMarker = true;
+                taken.Add(list[i]);
             }
-            if (removedLast)
+            list.RemoveRange(from, list.Count - from);
+
+            if (tookLastPlatformMarker)
             {
                 _lastPlatformMarker = null;
                 for (var i = list.Count - 1; i >= 0; i--)
@@ -449,6 +611,28 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                     }
                 }
             }
+            return taken;
+        }
+
+        private void InvalidateInvocationMarkersFrom(string fileName, long offset) => TakeInvocationMarkersFrom(fileName, offset, out _);
+
+        /// <summary>
+        /// An entry that reads unchanged after a rewind keeps its markers: gives back the set-aside markers at exactly
+        /// <paramref name="entryOffset"/>. Set-aside markers in front of it belonged to entries that changed and stay
+        /// gone with their bytes.
+        /// </summary>
+        private void RestoreInvocationMarkers(RewindState rewind, long entryOffset)
+        {
+            var markers = rewind.Markers;
+            while (rewind.Next < markers.Count && markers[rewind.Next].Offset < entryOffset) rewind.Next++;
+            while (rewind.Next < markers.Count && markers[rewind.Next].Offset == entryOffset)
+            {
+                var marker = markers[rewind.Next++];
+                var list = GetOrCreateMarkerList(rewind.FileName);
+                if (list.Count > 0 && list[list.Count - 1].Offset >= marker.Offset) continue;
+                AppendInvocationMarker(list, marker);
+                if (ReferenceEquals(marker, rewind.LastPlatformMarker)) _lastPlatformMarker = marker;
+            }
         }
 
         private long OldestPendingScriptMarkerOffset(string fileName)
@@ -474,6 +658,9 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         /// <summary>What a rollover of the file does to its invocation markers.</summary>
         internal void ClearInvocationMarkersForTest(string fileName) => InvalidateInvocationMarkersFrom(fileName, 0);
 
+        internal int InvocationMarkerCountForTest(string fileName)
+            => _invocationMarkers.TryGetValue(fileName, out var list) ? list.Count : 0;
+
         internal int LedgerEntryCountForTest(string fileName)
         {
             FileLedger ledger;

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/Ime/ImeLogTracker.cs

@@ -182,6 +182,19 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         private readonly Dictionary<string, ScriptExecutionState> _pendingPlatformScripts =
             new Dictionary<string, ScriptExecutionState>(StringComparer.OrdinalIgnoreCase);
 
+        // Earlier runs of a policy whose next executor run started before IME's result of them was
+        // read (IME re-runs a failed script on later check-ins; the first pass reads all of
+        // AgentExecutor.log before the IME log). Each keeps its own end block until its result
+        // arrives — session eff1b413 lost that and paired the first result with the last run's block.
+        private readonly List<ScriptExecutionState> _parkedPlatformScripts = new List<ScriptExecutionState>();
+        private const int MaxParkedPlatformScripts = 64;
+
+        /// <summary>
+        /// The platform runs this tracker started and emitted, for the registry reconciliation that
+        /// checks them against IME's saved results (D-316). Shared with the registry host's thread.
+        /// </summary>
+        internal PlatformScriptRunRegister ScriptRuns { get; } = new PlatformScriptRunRegister();
+
         // Health-script (remediation) line-by-line accumulator — single slot because IME
         // executes health scripts SEQUENTIALLY within a session (verified across multiple
         // diagnostic captures: ProcessScript → context → exit → stdout → stderr → compliance,
@@ -240,7 +253,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         // the 32K-char Table Storage property limit that bounds the event downstream. Growth
         // driver is the number of log lines the bootstrap chain writes, so re-measure before
         // adding a chatty step rather than raising this again.
-        private const int MaxScriptOutputLength = 8192;
+        internal const int MaxScriptOutputLength = 8192;
+        internal const string OutputTruncationMarker = "...[truncated]";
         private const int MaxMultiLineBufferLines = 100;
         // Size cap for ONE entry — a single physical line (enforced by BoundedLineReader before
         // the line is materialized) and an assembled multiline entry alike. Any process able to
@@ -389,6 +403,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                     VerifiedBytes = _verifiedBytes,
                     PassMaxMs = _passMaxMs,
                     PassGapMaxMs = _passGapMaxMs,
+                    PlatformOutputVerified = ScriptRuns.Verified,
+                    PlatformOutputCorrected = ScriptRuns.Corrected,
                     PatternHits = new Dictionary<string, int>(_patternHits, StringComparer.OrdinalIgnoreCase),
                 };
             }
@@ -1034,6 +1050,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         internal async Task RunPollPassAsync(CancellationToken token)
         {
             var startMs = MonotonicMillisProvider();
+            var passStartedUtc = UtcNowProvider();
             if (_lastPassEndMs >= 0 && startMs - _lastPassEndMs > _passGapMaxMs)
             {
                 _passGapMaxMs = startMs - _lastPassEndMs;
@@ -1045,6 +1062,12 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
             FlushRecurringScripts(UtcNowProvider(), shuttingDown: false);
             CheckPendingTokenFailure(UtcNowProvider());
 
+            // The lines written before this pass started are read now — a held tail or a fragment
+            // awaiting its check follows a pass or two later, which TrackerCatchUp covers. The
+            // registry reconciliation waits for such a pass before it pairs an IME save with a run.
+            if (!token.IsCancellationRequested) ScriptRuns.NotePassCompleted(passStartedUtc);
+            if (ScriptRuns.ConsumeCountersChanged()) _stateDirty = true;
+
             var endMs = MonotonicMillisProvider();
             if (endMs - startMs > _passMaxMs)
             {
@@ -1175,6 +1198,16 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                 }
             }
 
+            _parkedPlatformScripts.Clear();
+            if (state.ParkedPlatformScripts != null)
+            {
+                foreach (var parked in state.ParkedPlatformScripts)
+                {
+                    if (!string.IsNullOrEmpty(parked?.PolicyId) && _parkedPlatformScripts.Count < MaxParkedPlatformScripts)
+                        _parkedPlatformScripts.Add(parked);
+                }
+            }
+
             _scriptTimeoutSuspectedPosted.Clear();
             if (state.ScriptTimeoutSuspectedPosted != null)
             {
@@ -1207,6 +1240,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                     _verifiedBytes = state.Health.VerifiedBytes;
                     _passMaxMs = state.Health.PassMaxMs;
                     _passGapMaxMs = state.Health.PassGapMaxMs;
+                    ScriptRuns.RestoreCounters(state.Health.PlatformOutputVerified, state.Health.PlatformOutputCorrected);
                 }
                 if (state.PatternHits != null)
                 {
@@ -1259,6 +1293,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                 // must survive restarts — see the LoadState comment for the duplicate scenario.
                 PlatformScriptResultEmittedAt = new Dictionary<string, DateTime>(_platformScriptResultEmitted, StringComparer.OrdinalIgnoreCase),
                 PendingPlatformScripts = _pendingPlatformScripts.Values.ToList(),
+                ParkedPlatformScripts = _parkedPlatformScripts.ToList(),
                 ScriptTimeoutSuspectedPosted = _scriptTimeoutSuspectedPosted.ToList(),
                 RecurringScripts = _recurringScripts.ToPersisted(),
             };
@@ -1283,6 +1318,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
                     VerifiedBytes = _verifiedBytes,
                     PassMaxMs = _passMaxMs,
                     PassGapMaxMs = _passGapMaxMs,
+                    PlatformOutputVerified = ScriptRuns.Verified,
+                    PlatformOutputCorrected = ScriptRuns.Corrected,
                 };
                 state.PatternHits = new Dictionary<string, int>(_patternHits, StringComparer.OrdinalIgnoreCase);
             }

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/Ime/ImeTrackerHealth.cs

@@ -81,6 +81,16 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         /// </summary>
         public long PassGapMaxMs { get; set; }
 
+        /// <summary>
+        /// Platform-script runs whose emitted output IME's saved result (registry, after the batch
+        /// report) confirmed — the exit code of the same end block with it. Together with
+        /// <see cref="PlatformOutputCorrected"/> the field measure of the registry reconciliation (D-316).
+        /// </summary>
+        public long PlatformOutputVerified { get; set; }
+
+        /// <summary>Platform-script runs whose emitted output IME's saved result corrected (script_output_reconciliation).</summary>
+        public long PlatformOutputCorrected { get; set; }
+
         /// <summary>Match count per enabled pattern ID — every enabled pattern is present, zeros included.</summary>
         public IReadOnlyDictionary<string, int> PatternHits { get; set; }
 

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/Ime/ImeTrackerStatePersistence.cs

@@ -151,6 +151,10 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         // that run from the start of the next one.
         public Dictionary<string, DateTime> PlatformScriptResultEmittedAt { get; set; }
         public List<ScriptExecutionState> PendingPlatformScripts { get; set; }
+        // Earlier runs that wait for their IME result while a later run of the same policy is in
+        // flight; a restart between reading AgentExecutor.log and the IME log must keep them. Null on
+        // older state files → none.
+        public List<ScriptExecutionState> ParkedPlatformScripts { get; set; }
         public List<string> ScriptTimeoutSuspectedPosted { get; set; }
 
         // Recurring health-script runs collapsed per policy. Saved in the same write as
@@ -185,6 +189,9 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
         // Poll-loop timing maxima (null-defaulting on older state files).
         public long PassMaxMs { get; set; }
         public long PassGapMaxMs { get; set; }
+        // Registry reconciliation of platform-script output (null-defaulting on older state files).
+        public long PlatformOutputVerified { get; set; }
+        public long PlatformOutputCorrected { get; set; }
     }
 
     public class PackageStateData

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/Ime/PlatformScriptRunRegister.cs

@@ -0,0 +1,196 @@
+using System;
+using System.Collections.Generic;
+
+namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime
+{
+    /// <summary>What the registry reconciliation may do with a saved IME result right now.</summary>
+    internal enum PlatformRunClaim
+    {
+        /// <summary>The run is handed out for reconciliation; it is never handed out again.</summary>
+        Claimed,
+        /// <summary>Not decidable yet: the tracker has not read past the save, or the run is not emitted yet.</summary>
+        Wait,
+        /// <summary>No run of this agent owns the save (none seen, or already reconciled).</summary>
+        None,
+    }
+
+    /// <summary>One platform-script run as the tracker emitted it; the register hands out copies.</summary>
+    internal sealed class PlatformScriptRun
+    {
+        public string PolicyId;
+        public string UserId;
+        public string RunId;
+        public DateTime StartSeenUtc;
+        public bool Emitted;
+        public bool Claimed;
+        public string Result;
+        public string ResultSource;
+        public int? ExitCode;
+        /// <summary>As emitted: null when no output line of the run was read, empty when it said so.</summary>
+        public string Stdout;
+        public string Stderr;
+
+        public PlatformScriptRun Clone() => (PlatformScriptRun)MemberwiseClone();
+    }
+
+    /// <summary>
+    /// The platform-script runs the tracker has seen, the latest per (IME user id, policy id), for the
+    /// registry reconciliation (D-316). IME saves a run's output under
+    /// <c>Policies\&lt;UserId&gt;\&lt;PolicyId&gt;</c> only after it reported the whole script batch, so the
+    /// observer reading it must know which run a changed key belongs to and what was emitted for it.
+    /// Written on the tracker's poll thread, claimed on the registry host's timer thread: every member
+    /// locks, and nothing calls out while holding the lock.
+    /// <para>
+    /// A save belongs to the latest run of its key: IME runs a policy at most once per check-in and
+    /// saves after reporting that check-in's batch, so the next run of the key comes with a later
+    /// check-in. (Overlapping check-ins can run a key twice at once; then IME itself shares the key's
+    /// result files and the judge's foreign verdict is the safety net.) A run that waited for its IME
+    /// result while a later run of its key already started is emitted without touching that later
+    /// run's entry. A save is paired only after the tracker completed a pass that started
+    /// <see cref="TrackerCatchUp"/> after the save was seen — every line written before the save, the
+    /// run's start among them, has been read by then, a stalled poll loop included.
+    /// </para>
+    /// </summary>
+    internal sealed class PlatformScriptRunRegister
+    {
+        /// <summary>
+        /// How far behind a seen save the tracker must have started a completed pass before the save
+        /// is paired; covers the ledger's verify cadence (1 s) for a start line hidden by an overwrite.
+        /// </summary>
+        internal static readonly TimeSpan TrackerCatchUp = TimeSpan.FromSeconds(2);
+
+        internal const int MaxRuns = 256;
+
+        private readonly object _sync = new object();
+        private readonly Dictionary<string, PlatformScriptRun> _latest =
+            new Dictionary<string, PlatformScriptRun>(StringComparer.OrdinalIgnoreCase);
+        private DateTime _lastCompletedPassStartUtc = DateTime.MinValue;
+        private long _verified;
+        private long _corrected;
+        private bool _countersChanged;
+
+        private static string KeyOf(string userId, string policyId) => (userId ?? string.Empty) + "|" + policyId;
+
+        /// <summary>A platform run began: its start line, or its result when no start line was seen.</summary>
+        public void NoteStarted(string userId, string policyId, DateTime seenUtc)
+        {
+            if (string.IsNullOrEmpty(policyId)) return;
+            lock (_sync)
+            {
+                _latest[KeyOf(userId, policyId)] = new PlatformScriptRun { PolicyId = policyId, UserId = userId, StartSeenUtc = seenUtc };
+                TrimLocked();
+            }
+        }
+
+        /// <summary>The tracker emitted the run with these end-block values.</summary>
+        public void NoteEmitted(ScriptExecutionState script, DateTime emittedUtc)
+        {
+            if (script == null || string.IsNullOrEmpty(script.PolicyId)) return;
+            lock (_sync)
+            {
+                var key = KeyOf(script.UserId, script.PolicyId);
+                if (!_latest.TryGetValue(key, out var run) || run.Emitted)
+                {
+                    run = new PlatformScriptRun { PolicyId = script.PolicyId, UserId = script.UserId, StartSeenUtc = emittedUtc };
+                    _latest[key] = run;
+                }
+                run.Emitted = true;
+                run.RunId = script.RunId;
+                run.Result = script.Result;
+                run.ResultSource = script.ResultSource;
+                run.ExitCode = script.ExitCode;
+                run.Stdout = script.Stdout;
+                run.Stderr = script.Stderr;
+                TrimLocked();
+            }
+        }
+
+        /// <summary>The tracker finished a poll pass that started at <paramref name="passStartedUtc"/>.</summary>
+        public void NotePassCompleted(DateTime passStartedUtc)
+        {
+            lock (_sync)
+            {
+                if (passStartedUtc > _lastCompletedPassStartUtc) _lastCompletedPassStartUtc = passStartedUtc;
+            }
+        }
+
+        /// <summary>
+        /// Hands out the run a save of (<paramref name="userId"/>, <paramref name="policyId"/>) seen at
+        /// <paramref name="savedSeenUtc"/> belongs to — once. A run whose user id the tracker could not
+        /// read is keyed without one.
+        /// </summary>
+        public PlatformRunClaim TryClaim(string userId, string policyId, DateTime savedSeenUtc, out PlatformScriptRun run)
+        {
+            run = null;
+            lock (_sync)
+            {
+                if (_lastCompletedPassStartUtc < savedSeenUtc + TrackerCatchUp) return PlatformRunClaim.Wait;
+
+                if (!_latest.TryGetValue(KeyOf(userId, policyId), out var latest)
+                    && !_latest.TryGetValue(KeyOf(null, policyId), out latest))
+                    return PlatformRunClaim.None;
+                if (latest.Claimed) return PlatformRunClaim.None;
+                if (!latest.Emitted) return PlatformRunClaim.Wait;
+
+                latest.Claimed = true;
+                run = latest.Clone();
+                return PlatformRunClaim.Claimed;
+            }
+        }
+
+        public void CountVerified()
+        {
+            lock (_sync) { _verified++; _countersChanged = true; }
+        }
+
+        public void CountCorrected()
+        {
+            lock (_sync) { _corrected++; _countersChanged = true; }
+        }
+
+        /// <summary>Runs whose emitted output IME's saved result confirmed (restart-safe, session-cumulative).</summary>
+        public long Verified { get { lock (_sync) return _verified; } }
+
+        /// <summary>Runs whose emitted output IME's saved result corrected (restart-safe, session-cumulative).</summary>
+        public long Corrected { get { lock (_sync) return _corrected; } }
+
+        public void RestoreCounters(long verified, long corrected)
+        {
+            lock (_sync)
+            {
+                _verified = verified;
+                _corrected = corrected;
+            }
+        }
+
+        /// <summary>True once after a counter moved — the tracker then persists its state.</summary>
+        public bool ConsumeCountersChanged()
+        {
+            lock (_sync)
+            {
+                var changed = _countersChanged;
+                _countersChanged = false;
+                return changed;
+            }
+        }
+
+        private void TrimLocked()
+        {
+            while (_latest.Count > MaxRuns)
+            {
+                string oldestKey = null;
+                var oldest = DateTime.MaxValue;
+                foreach (var kv in _latest)
+                {
+                    if (kv.Value.StartSeenUtc < oldest)
+                    {
+                        oldest = kv.Value.StartSeenUtc;
+                        oldestKey = kv.Key;
+                    }
+                }
+                if (oldestKey == null) return;
+                _latest.Remove(oldestKey);
+            }
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/Ime/ScriptExecutionState.cs

@@ -15,6 +15,28 @@ public class ScriptExecutionState
     /// <summary>"platform" or "remediation".</summary>
     public string ScriptType { get; set; }
 
+    /// <summary>
+    /// IME user id a platform script ran for (the all-zero GUID in device context), read from its
+    /// script path or its result line. Keys IME's saved result
+    /// (<c>Policies\&lt;UserId&gt;\&lt;PolicyId&gt;</c>) that the registry reconciliation compares against.
+    /// </summary>
+    public string UserId { get; set; }
+
+    /// <summary>
+    /// Identity of one platform-script run, given when its slot opens and surfaced as <c>runId</c> on
+    /// the event: the invocation markers bind the run's executor lines to it, and a later
+    /// <c>script_output_reconciliation</c> names it when it corrects that run.
+    /// </summary>
+    public string RunId { get; set; }
+
+    /// <summary>
+    /// Source timestamp of the run's AgentExecutor start line (<c>Adding argument powershell with
+    /// value …</c>). Every executor process writes that line once, so a later one for the same
+    /// policy starts the next run, never this one. Null until the line is read, and on state files
+    /// from before the field.
+    /// </summary>
+    public System.DateTime? ExecutorStartedAtUtc { get; set; }
+
     /// <summary>
     /// UTC timestamp of the script's first observed start line, taken from the source CMTrace log
     /// timestamp (so it dates correctly even when the agent replays historic IME log content that

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/SystemSignals/ImeRegistryScriptResultObserver.cs

@@ -0,0 +1,401 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Text.Json;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.DecisionCore.Engine;
+using AutopilotMonitor.Shared.Models;
+using Microsoft.Win32;
+using SharedEventTypes = AutopilotMonitor.Shared.Constants.EventTypes;
+
+namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals
+{
+    /// <summary>
+    /// Registry second pillar for platform scripts (D-316). After IME reported a script batch to
+    /// Intune it saves every run of the batch under
+    /// <c>HKLM\SOFTWARE\Microsoft\IntuneManagementExtension\Policies\&lt;UserId&gt;\&lt;PolicyId&gt;</c>:
+    /// <c>Result</c>, <c>ErrorCode</c> and <c>ResultDetails</c>, whose <c>ExecutionMsg</c> is what IME read
+    /// from the result file of exactly that policy — the stdout when the run succeeded (IME's Success
+    /// means an empty stderr file, whatever the exit code), the stderr when it failed with ErrorCode 99.
+    /// The log tracker assigns a run's exit code and output by file position in AgentExecutor.log, where
+    /// no policy id anchors them; this observer checks what was emitted against the keyed value and
+    /// emits <c>script_output_reconciliation</c> when they disagree.
+    /// <para>
+    /// Snapshot-and-diff like <see cref="ImeRegistryAppStateObserver"/>, ticked by the same host: the
+    /// first tick is the silent baseline, a later save is paired with its run through
+    /// <see cref="PlatformScriptRunRegister"/>. No exit code lives in the registry: a run whose output
+    /// matches proves the exit code of the same end block; a contradicted run loses its exit code.
+    /// </para>
+    /// </summary>
+    internal sealed class ImeRegistryScriptResultObserver
+    {
+        public const string SourceLabel = "RegistryScriptResult";
+
+        internal const string PoliciesKeyPath = ImeRegistryAppStateObserver.ImeRootKeyPath + @"\Policies";
+
+        /// <summary>A save whose run never became claimable is dropped after this long (send failure of a later batch, agent restart).</summary>
+        internal static readonly TimeSpan PendingExpiry = TimeSpan.FromMinutes(10);
+
+        /// <summary>Safety cap on correction events per agent run; corrections beyond it are counted only.</summary>
+        internal const int MaxCorrectionsPerSession = 100;
+
+        private readonly PlatformScriptRunRegister _runs;
+        private readonly Func<IReadOnlyDictionary<string, SavedScriptResult>> _snapshotSource;
+        private readonly InformationalEventPost _post;
+        private readonly AgentLogger? _logger;
+        private readonly IClock _clock;
+        private readonly object _sync = new object();
+
+        private IReadOnlyDictionary<string, SavedScriptResult>? _last;
+        private readonly Dictionary<string, (SavedScriptResult Saved, DateTime SeenUtc)> _pending =
+            new Dictionary<string, (SavedScriptResult, DateTime)>(StringComparer.OrdinalIgnoreCase);
+        private int _correctionsEmitted;
+
+        /// <param name="snapshotSource">Replaces the live registry walk in tests; per instance, so parallel test classes never share it.</param>
+        public ImeRegistryScriptResultObserver(
+            PlatformScriptRunRegister runs,
+            InformationalEventPost post,
+            AgentLogger? logger,
+            IClock clock,
+            Func<IReadOnlyDictionary<string, SavedScriptResult>>? snapshotSource = null)
+        {
+            _runs = runs ?? throw new ArgumentNullException(nameof(runs));
+            _post = post ?? throw new ArgumentNullException(nameof(post));
+            _clock = clock ?? throw new ArgumentNullException(nameof(clock));
+            _logger = logger;
+            _snapshotSource = snapshotSource ?? ReadSnapshot;
+        }
+
+        /// <summary>One observation pass: snapshot → new saves → pair → judge → correct. Fail-soft: never throws.</summary>
+        public void Tick(string reason)
+        {
+            try
+            {
+                lock (_sync)
+                {
+                    var snapshot = _snapshotSource();
+                    var nowUtc = _clock.UtcNow;
+
+                    if (_last == null)
+                    {
+                        // Saves that predate this agent run belong to runs it never emitted.
+                        _last = snapshot;
+                        _logger?.Info($"RegistryScriptResult: baseline captured ({snapshot.Count} saved platform-script results, trigger={reason})");
+                        return;
+                    }
+
+                    foreach (var kv in snapshot)
+                    {
+                        if (_last.TryGetValue(kv.Key, out var previous) && previous.SameSaveAs(kv.Value)) continue;
+                        _pending[kv.Key] = (kv.Value, nowUtc); // a newer save of the key replaces a waiting one
+                    }
+                    _last = snapshot;
+
+                    ProcessPending(nowUtc);
+                }
+            }
+            catch (Exception ex)
+            {
+                _logger?.Debug($"RegistryScriptResult: tick failed (fail-soft): {ex.Message}");
+            }
+        }
+
+        private void ProcessPending(DateTime nowUtc)
+        {
+            foreach (var key in _pending.Keys.ToList())
+            {
+                var (saved, seenUtc) = _pending[key];
+                var claim = _runs.TryClaim(saved.UserId, saved.PolicyId, seenUtc, out var run);
+                if (claim == PlatformRunClaim.Wait)
+                {
+                    if (nowUtc - seenUtc >= PendingExpiry) _pending.Remove(key);
+                    continue;
+                }
+
+                _pending.Remove(key);
+                if (claim == PlatformRunClaim.Claimed && run != null) Reconcile(run, saved, nowUtc);
+            }
+        }
+
+        private void Reconcile(PlatformScriptRun run, SavedScriptResult saved, DateTime nowUtc)
+        {
+            var judgement = PlatformOutputJudge.Judge(run, saved);
+            switch (judgement.Verdict)
+            {
+                case PlatformOutputVerdict.Verified:
+                    _runs.CountVerified();
+                    _logger?.Debug($"RegistryScriptResult: platform script {run.PolicyId} output confirmed by IME's saved result");
+                    return;
+                case PlatformOutputVerdict.NotComparable:
+                    _logger?.Debug($"RegistryScriptResult: platform script {run.PolicyId} not comparable ({judgement.Reason})");
+                    return;
+            }
+
+            _runs.CountCorrected();
+            if (_correctionsEmitted >= MaxCorrectionsPerSession)
+            {
+                _logger?.Warning($"RegistryScriptResult: correction for {run.PolicyId} not emitted — cap of {MaxCorrectionsPerSession} per agent run reached");
+                return;
+            }
+            _correctionsEmitted++;
+
+            var foreign = judgement.Verdict == PlatformOutputVerdict.Foreign;
+            var culture = CultureInfo.InvariantCulture;
+            var data = new Dictionary<string, string>(StringComparer.Ordinal)
+            {
+                ["policyId"] = run.PolicyId,
+                ["scriptType"] = "platform",
+                ["outcome"] = foreign ? "foreign" : "repaired",
+                ["reason"] = judgement.Reason,
+            };
+            if (!string.IsNullOrEmpty(run.RunId)) data["runId"] = run.RunId!;
+            if (!string.IsNullOrEmpty(saved.Result)) data["result"] = saved.Result!;
+            if (saved.ErrorCode.HasValue) data["registryErrorCode"] = saved.ErrorCode.Value.ToString(culture);
+            // A present key replaces the emitted value, an empty one clears it; an absent key keeps it.
+            if (judgement.Stdout != null) data["stdout"] = judgement.Stdout;
+            if (judgement.Stderr != null) data["stderr"] = judgement.Stderr;
+            if (foreign && run.ExitCode.HasValue) data["previousExitCode"] = run.ExitCode.Value.ToString(culture);
+
+            var shortId = run.PolicyId.Length > 8 ? run.PolicyId.Substring(0, 8) : run.PolicyId;
+            var message = foreign
+                ? $"Platform script {shortId}: output corrected from IME's saved result; the log had attributed another script's output, exit code unverified"
+                : $"Platform script {shortId}: output completed from IME's saved result";
+
+            _post.Emit(
+                eventType: SharedEventTypes.ScriptOutputReconciliation,
+                source: SourceLabel,
+                message: message,
+                severity: foreign ? EventSeverity.Warning : EventSeverity.Info,
+                immediateUpload: foreign,
+                data: data,
+                occurredAtUtc: nowUtc);
+
+            if (foreign)
+                _logger?.Warning($"RegistryScriptResult: platform script {run.PolicyId} run {run.RunId} carried another script's end block ({judgement.Reason}) — corrected from IME's saved result");
+            else
+                _logger?.Info($"RegistryScriptResult: platform script {run.PolicyId} run {run.RunId} output completed from IME's saved result ({judgement.Reason})");
+        }
+
+        // ── snapshot ────────────────────────────────────────────────────────────
+
+        internal static string KeyOf(string userId, string policyId) => userId + "|" + policyId;
+
+        internal static IReadOnlyDictionary<string, SavedScriptResult> ReadSnapshot()
+        {
+            var snapshot = new Dictionary<string, SavedScriptResult>(StringComparer.OrdinalIgnoreCase);
+            using var baseKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry64);
+            using var policies = baseKey.OpenSubKey(PoliciesKeyPath);
+            if (policies == null) return snapshot;
+
+            foreach (var userId in policies.GetSubKeyNames())
+            {
+                if (!Guid.TryParse(userId, out _)) continue;
+                using var userKey = policies.OpenSubKey(userId);
+                if (userKey == null) continue;
+
+                foreach (var policyId in userKey.GetSubKeyNames())
+                {
+                    if (!Guid.TryParse(policyId, out _)) continue;
+                    using var policyKey = userKey.OpenSubKey(policyId);
+                    if (policyKey == null) continue;
+
+                    snapshot[KeyOf(userId, policyId)] = new SavedScriptResult
+                    {
+                        UserId = userId,
+                        PolicyId = policyId,
+                        Result = policyKey.GetValue("Result") as string,
+                        ErrorCode = TryReadInt(policyKey.GetValue("ErrorCode")),
+                        ResultDetails = policyKey.GetValue("ResultDetails") as string,
+                        LastUpdatedTimeUtc = policyKey.GetValue("LastUpdatedTimeUtc") as string,
+                    };
+                }
+            }
+            return snapshot;
+        }
+
+        private static int? TryReadInt(object? value)
+        {
+            switch (value)
+            {
+                case int i: return i;
+                case long l when l >= int.MinValue && l <= int.MaxValue: return (int)l;
+                case string s when int.TryParse(s, NumberStyles.Integer, CultureInfo.InvariantCulture, out var parsed): return parsed;
+                default: return null;
+            }
+        }
+    }
+
+    /// <summary>One platform-script result as IME saved it under <c>Policies\&lt;UserId&gt;\&lt;PolicyId&gt;</c>.</summary>
+    internal sealed class SavedScriptResult
+    {
+        public string UserId { get; set; } = string.Empty;
+        public string PolicyId { get; set; } = string.Empty;
+        public string? Result { get; set; }
+        public int? ErrorCode { get; set; }
+        public string? ResultDetails { get; set; }
+        public string? LastUpdatedTimeUtc { get; set; }
+
+        /// <summary>The same save: IME stamps every save with a new <c>LastUpdatedTimeUtc</c>.</summary>
+        public bool SameSaveAs(SavedScriptResult other)
+            => string.Equals(LastUpdatedTimeUtc, other.LastUpdatedTimeUtc, StringComparison.Ordinal)
+            && string.Equals(Result, other.Result, StringComparison.Ordinal)
+            && ErrorCode == other.ErrorCode
+            && string.Equals(ResultDetails, other.ResultDetails, StringComparison.Ordinal);
+
+        /// <summary>
+        /// <c>ExecutionMsg</c> of the CryptoResult JSON in <c>ResultDetails</c> (IME 1.73 and later), or null
+        /// when the value is not that JSON ("Hash mismatch", a launch failure).
+        /// </summary>
+        public string? ExecutionMessage()
+        {
+            if (string.IsNullOrWhiteSpace(ResultDetails)) return null;
+            try
+            {
+                using var doc = JsonDocument.Parse(ResultDetails!);
+                if (doc.RootElement.ValueKind != JsonValueKind.Object) return null;
+                return doc.RootElement.TryGetProperty("ExecutionMsg", out var msg) && msg.ValueKind == JsonValueKind.String
+                    ? msg.GetString()
+                    : null;
+            }
+            catch (JsonException)
+            {
+                return null;
+            }
+        }
+    }
+
+    internal enum PlatformOutputVerdict
+    {
+        /// <summary>IME's saved result cannot confirm or contradict the run (no output saved, other failure kind).</summary>
+        NotComparable,
+        /// <summary>The emitted output is what IME saved: the end block, its exit code included, is the run's own.</summary>
+        Verified,
+        /// <summary>The log delivered the run's output incomplete; IME's saved text completes it, the exit code stands.</summary>
+        Repaired,
+        /// <summary>The emitted output contradicts IME's saved result: the end block was another executor's.</summary>
+        Foreign,
+    }
+
+    internal sealed class PlatformOutputJudgement
+    {
+        public PlatformOutputVerdict Verdict { get; set; }
+        public string Reason { get; set; } = string.Empty;
+        /// <summary>Value to publish (Repaired/Foreign): null keeps the emitted stdout, empty clears it.</summary>
+        public string? Stdout { get; set; }
+        /// <summary>Value to publish (Repaired/Foreign): null keeps the emitted stderr, empty clears it.</summary>
+        public string? Stderr { get; set; }
+    }
+
+    /// <summary>
+    /// Compares a platform-script run as the tracker emitted it with IME's saved result. Comparable are
+    /// a Success (ExecutionMsg = stdout; IME's Success means the stderr file was empty) and a Failed with
+    /// ErrorCode 99 (ExecutionMsg = stderr). Both texts are compared after CR/LF normalisation and Trim;
+    /// the tracker's own 8192-character cut is a prefix of the saved text.
+    /// </summary>
+    internal static class PlatformOutputJudge
+    {
+        internal const int ImeStderrErrorCode = 99;
+        private const string OutputErrorSeparator = ", error =";
+
+        public static PlatformOutputJudgement Judge(PlatformScriptRun run, SavedScriptResult saved)
+        {
+            var executionMessage = saved.ExecutionMessage();
+            if (executionMessage == null) return NotComparable("no_execution_message");
+
+            // The run's IME result line and the save come from the same IME run.
+            if (string.Equals(run.ResultSource, "ime_policy_result", StringComparison.Ordinal)
+                && !string.Equals(run.Result, saved.Result, StringComparison.OrdinalIgnoreCase))
+                return NotComparable("result_differs");
+
+            if (string.Equals(saved.Result, "Success", StringComparison.OrdinalIgnoreCase))
+                return JudgeSuccess(run, Normalize(executionMessage)!);
+            if (string.Equals(saved.Result, "Failed", StringComparison.OrdinalIgnoreCase) && saved.ErrorCode == ImeStderrErrorCode)
+                return JudgeStderrFailure(run, Normalize(executionMessage)!);
+            return NotComparable("no_saved_output");
+        }
+
+        private static PlatformOutputJudgement JudgeSuccess(PlatformScriptRun run, string savedStdout)
+        {
+            var stdout = NormalizeEmitted(run.Stdout, out var stdoutCut);
+            var stderr = Normalize(run.Stderr);
+            var stderrClean = string.IsNullOrEmpty(stderr);
+
+            if (!string.IsNullOrEmpty(stdout) && Agrees(stdout!, stdoutCut, savedStdout))
+                return stderrClean ? Verified() : Correct(PlatformOutputVerdict.Repaired, "stderr_cleared", savedStdout, string.Empty);
+
+            if (stdout != null && stdout.Length == 0 && savedStdout.Length == 0)
+                return stderrClean ? Verified() : Correct(PlatformOutputVerdict.Foreign, "stderr_on_success", string.Empty, string.Empty);
+
+            if (stdout == null)
+            {
+                if (!stderrClean) return Correct(PlatformOutputVerdict.Foreign, "stderr_on_success", savedStdout, string.Empty);
+                return savedStdout.Length > 0
+                    ? Correct(PlatformOutputVerdict.Repaired, "stdout_missing", savedStdout, string.Empty)
+                    : NotComparable("nothing_read");
+            }
+
+            // "write output done. output = X, error = Y" splits at the first ", error =" — a stdout that
+            // contains the separator ends up partly in stderr. The saved text shows the cut right there.
+            if (stdout.Length > 0 && !stdoutCut && !stderrClean
+                && savedStdout.StartsWith(stdout, StringComparison.Ordinal)
+                && savedStdout.Substring(stdout.Length).TrimStart().StartsWith(OutputErrorSeparator, StringComparison.Ordinal))
+                return Correct(PlatformOutputVerdict.Repaired, "stdout_split", savedStdout, string.Empty);
+
+            return Correct(PlatformOutputVerdict.Foreign, "stdout_differs", savedStdout, string.Empty);
+        }
+
+        private static PlatformOutputJudgement JudgeStderrFailure(PlatformScriptRun run, string savedStderr)
+        {
+            var stderr = NormalizeEmitted(run.Stderr, out var stderrCut);
+            if (!string.IsNullOrEmpty(stderr) && Agrees(stderr!, stderrCut, savedStderr)) return Verified();
+
+            // Nothing of the end block read: complete the stderr, the run's stdout stays as emitted.
+            if (run.Stderr == null && run.Stdout == null)
+                return Correct(PlatformOutputVerdict.Repaired, "stderr_missing", null, savedStderr);
+
+            // The end block read said something else — an empty stderr included: IME read stderr from this
+            // run's error file. The block's stdout is the other executor's as well.
+            return Correct(PlatformOutputVerdict.Foreign, "stderr_differs", string.Empty, savedStderr);
+        }
+
+        private static bool Agrees(string emitted, bool emittedCut, string saved)
+            => string.Equals(emitted, saved, StringComparison.Ordinal)
+            || (emittedCut && saved.StartsWith(emitted, StringComparison.Ordinal));
+
+        /// <summary>CR LF and lone CR to LF, then Trim — what the tracker's line reader and handlers make of a text.</summary>
+        internal static string? Normalize(string? text)
+            => text?.Replace("\r\n", "\n").Replace('\r', '\n').Trim();
+
+        private static string? NormalizeEmitted(string? text, out bool cut)
+        {
+            cut = false;
+            if (text == null) return null;
+            if (text.EndsWith(ImeLogTracker.OutputTruncationMarker, StringComparison.Ordinal))
+            {
+                cut = true;
+                text = text.Substring(0, text.Length - ImeLogTracker.OutputTruncationMarker.Length);
+            }
+            return Normalize(text);
+        }
+
+        private static PlatformOutputJudgement Verified()
+            => new PlatformOutputJudgement { Verdict = PlatformOutputVerdict.Verified, Reason = "match" };
+
+        private static PlatformOutputJudgement NotComparable(string reason)
+            => new PlatformOutputJudgement { Verdict = PlatformOutputVerdict.NotComparable, Reason = reason };
+
+        private static PlatformOutputJudgement Correct(PlatformOutputVerdict verdict, string reason, string? stdout, string? stderr)
+            => new PlatformOutputJudgement
+            {
+                Verdict = verdict,
+                Reason = reason,
+                // The tracker's own output cap: a corrected value is never longer than an emitted one.
+                Stdout = stdout == null ? null : ImeLogTracker.TruncateOutput(stdout),
+                Stderr = stderr == null ? null : ImeLogTracker.TruncateOutput(stderr),
+            };
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/SystemSignals/ServicingTracker.cs

@@ -280,7 +280,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals
                 Timestamp = timeCreatedUtc ?? DateTime.UtcNow,
                 EventType = Constants.EventTypes.WindowsUpdateServicing,
                 Severity = severity,
-                Source = "ServicingWatcher",
+                Source = Constants.EventSources.ServicingWatcher,
                 Phase = EnrollmentPhase.Unknown,
                 Message = message,
                 Data = data,

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/SystemSignals/SystemTimelineTracker.cs

@@ -340,7 +340,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals
                 Timestamp = timeCreatedUtc ?? DateTime.UtcNow,
                 EventType = Constants.EventTypes.SystemClockChanged,
                 Severity = isLargeStep ? EventSeverity.Warning : EventSeverity.Info,
-                Source = "SystemTimelineWatcher",
+                Source = Constants.EventSources.SystemTimelineWatcher,
                 Phase = EnrollmentPhase.Unknown,
                 Message = message,
                 Data = data,
@@ -467,7 +467,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals
                 Timestamp = timeCreatedUtc ?? DateTime.UtcNow,
                 EventType = Constants.EventTypes.SystemSleepEpisode,
                 Severity = EventSeverity.Info,
-                Source = "SystemTimelineWatcher",
+                Source = Constants.EventSources.SystemTimelineWatcher,
                 Phase = EnrollmentPhase.Unknown,
                 Message = message,
                 Data = data,

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Enrollment/SystemSignals/WindowsUpdateTracker.cs

@@ -405,7 +405,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals
                 Timestamp = timeCreatedUtc ?? DateTime.UtcNow,
                 EventType = shape.EventType,
                 Severity = shape.Severity,
-                Source = "WindowsUpdateWatcher",
+                Source = Constants.EventSources.WindowsUpdateWatcher,
                 Phase = EnrollmentPhase.Unknown,
                 Message = BuildMessage(eventId, title, updateCount, data),
                 Data = data,
@@ -707,7 +707,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals
                     TenantId = _tenantId,
                     EventType = Constants.EventTypes.WindowsUpdateChannelCensus,
                     Severity = EventSeverity.Debug,
-                    Source = "WindowsUpdateWatcher",
+                    Source = Constants.EventSources.WindowsUpdateWatcher,
                     Phase = EnrollmentPhase.Unknown,
                     Message = "Windows Update channel census: OS build changed across restart but no targeted WU events were captured — EventID histogram attached",
                     Data = data,

src/Agent/AutopilotMonitor.Agent.V2.Core/Monitoring/Telemetry/Periodic/AgentSelfMetricsCollector.cs

@@ -215,6 +215,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Periodic
                         data["ime_verified_bytes"] = health.VerifiedBytes;
                         data["ime_pass_max_ms"] = health.PassMaxMs;
                         data["ime_pass_gap_max_ms"] = health.PassGapMaxMs;
+                        data["ime_platform_output_verified"] = health.PlatformOutputVerified;
+                        data["ime_platform_output_corrected"] = health.PlatformOutputCorrected;
                     }
                 }
                 catch (Exception ex)

src/Agent/AutopilotMonitor.Agent.V2.Core/Orchestration/DefaultComponentFactory.cs

@@ -524,14 +524,17 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
             // EspTrackingWin32Apps, StatusServiceReports) via snapshot-and-diff. Emits
             // registry_app_state on real changes and app_state_reconciliation when the
             // registry outcome diverges from the IME-log-derived state (= built-in pattern-drift
-            // alarm). Always-on observability host; the tracker probe is read-only.
+            // alarm). Always-on observability host; the tracker probe is read-only. Under the same
+            // root IME saves each platform script's result after reporting the batch: the script
+            // observer checks the tracker's emitted runs against it (script_output_reconciliation).
             hosts.Add(new ImeRegistryAppStateHost(
                 sessionId: sessionId,
                 tenantId: tenantId,
                 logger: logger,
                 ingress: ingress,
                 clock: clock,
-                trackerStateProbe: () => imeLogHost.AllKnownPackageStates));
+                trackerStateProbe: () => imeLogHost.AllKnownPackageStates,
+                scriptRuns: imeLogHost.Tracker.ScriptRuns));
 
             // Deterministic update corroboration — compares the persisted OS build (CurrentBuild.UBR)
             // across agent restarts and emits os_build_changed when it differs (session 7443317c:

src/Agent/AutopilotMonitor.Agent.V2.Core/Orchestration/Hosts/ImeRegistryAppStateHost.cs

@@ -15,9 +15,10 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
 {
     /// <summary>
     /// Hosts the <see cref="ImeRegistryAppStateObserver"/> (registry second pillar, audit
-    /// 2026-08-17): one recursive <see cref="RegistryWatcher"/> on the IME root — all three
-    /// observed surfaces (Win32Apps, EspTrackingWin32Apps, SideCarPolicies\StatusServiceReports)
-    /// live under it — debounced into snapshot-and-diff ticks, plus a 60-s periodic fallback
+    /// 2026-08-17) and the <see cref="ImeRegistryScriptResultObserver"/> (D-316): one recursive
+    /// <see cref="RegistryWatcher"/> on the IME root — every observed surface (Win32Apps,
+    /// EspTrackingWin32Apps, SideCarPolicies\StatusServiceReports, Policies) lives under it —
+    /// debounced into snapshot-and-diff ticks, plus a 60-s periodic fallback
     /// tick. The fallback both evaluates the reconciliation settle-delay when the registry goes
     /// quiet AND keeps the pillar alive if the watcher fails to arm (poll-only degraded mode,
     /// announced once via <c>collector_degraded</c>). Always-on observability host, no config
@@ -31,6 +32,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
         private static readonly TimeSpan PeriodicInterval = TimeSpan.FromSeconds(60);
 
         private readonly ImeRegistryAppStateObserver _observer;
+        // Platform-script results under the same root (D-316); null when no run register was supplied.
+        private readonly ImeRegistryScriptResultObserver? _scriptObserver;
         private readonly InformationalEventPost _post;
         private readonly AgentLogger? _logger;
         private readonly string _sessionId;
@@ -47,7 +50,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
             AgentLogger? logger,
             ISignalIngressSink ingress,
             IClock clock,
-            Func<IReadOnlyList<AppPackageState>>? trackerStateProbe)
+            Func<IReadOnlyList<AppPackageState>>? trackerStateProbe,
+            PlatformScriptRunRegister? scriptRuns = null)
         {
             if (ingress == null) throw new ArgumentNullException(nameof(ingress));
             if (clock == null) throw new ArgumentNullException(nameof(clock));
@@ -56,6 +60,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
             _logger = logger;
             _post = new InformationalEventPost(ingress, clock);
             _observer = new ImeRegistryAppStateObserver(_post, logger, clock, trackerStateProbe);
+            if (scriptRuns != null) _scriptObserver = new ImeRegistryScriptResultObserver(scriptRuns, _post, logger, clock);
         }
 
         public void Start()
@@ -63,6 +68,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
             // Baseline immediately: pre-existing registry state must be captured silently
             // BEFORE the first change edge, or stale entries would replay as fresh events.
             _observer.Tick("baseline");
+            _scriptObserver?.Tick("baseline");
 
             try
             {
@@ -120,6 +126,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
             try
             {
                 _observer.Tick(reason);
+                _scriptObserver?.Tick(reason);
             }
             catch (Exception ex)
             {

src/Agent/AutopilotMonitor.Agent.V2.Core/Orchestration/Hosts/WindowsUpdateWatcherHost.cs

@@ -197,7 +197,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
                     TenantId = _tenantId,
                     EventType = SharedConstants.EventTypes.WindowsUpdateActivitySummary,
                     Severity = EventSeverity.Debug,
-                    Source = "WindowsUpdateWatcher",
+                    Source = SharedConstants.EventSources.WindowsUpdateWatcher,
                     Phase = EnrollmentPhase.Unknown,
                     Message = $"Update activity counted instead of listed: {total} event(s) " +
                         "(Store, Defender and other non-OS updates, repeated scan results, servicing of non-OS packages)",
@@ -223,7 +223,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
             _ingress.Post(
                 kind: DecisionSignalKind.OsUpdateActivity,
                 occurredAtUtc: DateTime.SpecifyKind(occurredAtUtc, DateTimeKind.Utc),
-                sourceOrigin: source == "servicing" ? "ServicingWatcher" : "WindowsUpdateWatcher",
+                sourceOrigin: source == "servicing" ? SharedConstants.EventSources.ServicingWatcher : SharedConstants.EventSources.WindowsUpdateWatcher,
                 evidence: new Evidence(
                     kind: EvidenceKind.Raw,
                     identifier: $"os-update-activity:{source}",

src/Agent/AutopilotMonitor.Agent.V2.Core/Orchestration/SignalActivityClassifier.cs

@@ -92,6 +92,9 @@ namespace AutopilotMonitor.Agent.V2.Core.Orchestration
             SharedConstants.EventTypes.ImePatternHits,
             // Bookkeeping of runs that were deliberately not reported as activity.
             SharedConstants.EventTypes.ScriptRecurrenceSummary,
+            // A correction of an already reported script run from IME's saved result (D-316):
+            // registry observation after the fact, not progress.
+            SharedConstants.EventTypes.ScriptOutputReconciliation,
             // Same for the update watchers' tally of Store/Defender/other update events (D-310):
             // emitted on stop, never progress. Windows/.NET update steps stay activity.
             SharedConstants.EventTypes.WindowsUpdateActivitySummary,

src/Agent/AutopilotMonitor.Agent.V2.Core/SignalAdapters/ImeLogTrackerAdapter.cs

@@ -1263,6 +1263,8 @@ namespace AutopilotMonitor.Agent.V2.Core.SignalAdapters
             // logged its result line before the deadline). Lets the UI/MCP flag fallback-grounded
             // platform-script completions. Platform scripts only — null for health scripts.
             if (!string.IsNullOrEmpty(script.ResultSource)) data["resultSource"] = script.ResultSource!;
+            // The run a later script_output_reconciliation corrects names it by this id (platform only).
+            if (!string.IsNullOrEmpty(script.RunId)) data["runId"] = script.RunId!;
             if (!string.IsNullOrEmpty(script.ComplianceResult)) data["complianceResult"] = script.ComplianceResult!;
             if (script.RemediationStatus.HasValue) data["remediationStatus"] = script.RemediationStatus.Value.ToString(culture);
             if (script.TargetType.HasValue) data["targetType"] = script.TargetType.Value.ToString(culture);

src/Agent/AutopilotMonitor.Agent.V2.Core/Termination/EnrollmentTerminationHandler.cs

@@ -599,6 +599,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Termination
                     ["verifiedBytes"] = health.VerifiedBytes,
                     ["passMaxMs"] = health.PassMaxMs,
                     ["passGapMaxMs"] = health.PassGapMaxMs,
+                    ["platformOutputVerified"] = health.PlatformOutputVerified,
+                    ["platformOutputCorrected"] = health.PlatformOutputCorrected,
                     ["agentVersion"] = _agentVersion ?? string.Empty,
                 };
                 if (!string.IsNullOrEmpty(health.ImeAgentVersion))

src/Backend/AutopilotMonitor.Functions.Tests/PlatformStatsPublishTests.cs

@@ -0,0 +1,45 @@
+using System.Globalization;
+using AutopilotMonitor.Functions.Services;
+
+namespace AutopilotMonitor.Functions.Tests;
+
+/// <summary>
+/// The versioned platform-stats file is served immutable for a year, so every publish must write
+/// a new name. Maintenance publishes every 2 hours; the per-day name it used to write was rewritten
+/// up to 12 times a day, and caches kept the first copy of the day.
+/// </summary>
+public class PlatformStatsPublishTests
+{
+    private static readonly DateTime Publish = new(2026, 10, 3, 6, 0, 4, DateTimeKind.Utc);
+
+    [Fact]
+    public void Versioned_file_name_carries_the_publish_instant_to_the_second()
+    {
+        Assert.Equal("platform-stats.2026-10-03T060004Z.json", MaintenanceService.PlatformStatsVersionedFileName(Publish));
+    }
+
+    [Fact]
+    public void Two_publishes_of_one_day_get_different_names()
+    {
+        var early = MaintenanceService.PlatformStatsVersionedFileName(new DateTime(2026, 10, 3, 2, 0, 3, DateTimeKind.Utc));
+        var later = MaintenanceService.PlatformStatsVersionedFileName(new DateTime(2026, 10, 3, 4, 0, 3, DateTimeKind.Utc));
+
+        Assert.NotEqual(early, later);
+    }
+
+    [Fact]
+    public void Versioned_file_name_ignores_the_current_culture()
+    {
+        var previous = CultureInfo.CurrentCulture;
+        try
+        {
+            // th-TH counts years in the Buddhist era (2569 for 2026).
+            CultureInfo.CurrentCulture = new CultureInfo("th-TH");
+            Assert.Equal("platform-stats.2026-10-03T060004Z.json", MaintenanceService.PlatformStatsVersionedFileName(Publish));
+        }
+        finally
+        {
+            CultureInfo.CurrentCulture = previous;
+        }
+    }
+}

src/Backend/AutopilotMonitor.Functions.Tests/ScriptOutputReconciliationClassificationTests.cs

@@ -0,0 +1,52 @@
+using System;
+using System.Collections.Generic;
+using AutopilotMonitor.Functions.Services;
+using AutopilotMonitor.Shared;
+using AutopilotMonitor.Shared.Models;
+using Xunit;
+
+namespace AutopilotMonitor.Functions.Tests;
+
+/// <summary>
+/// D-316: the agent corrects an already reported platform run from IME's saved result with a
+/// script_output_reconciliation. It is observation of an earlier run: it never heals a Stalled session and never
+/// counts as another script run.
+/// </summary>
+public class ScriptOutputReconciliationClassificationTests
+{
+    private static readonly DateTime At = new(2026, 10, 3, 20, 59, 8, DateTimeKind.Utc);
+
+    [Fact]
+    public void A_correction_alone_is_no_real_activity_and_no_script_run()
+    {
+        var classification = EventIngestProcessor.ClassifyEvents(new List<EnrollmentEvent>
+        {
+            Event(Constants.EventTypes.ScriptOutputReconciliation, new Dictionary<string, object> { ["scriptType"] = "platform", ["runId"] = "run-1", ["outcome"] = "foreign" }),
+        });
+
+        Assert.False(classification.HasNonPeriodicRealEvent);
+        Assert.Equal(0, classification.PlatformScriptCount);
+    }
+
+    [Fact]
+    public void The_corrected_run_counts_once_as_a_platform_script()
+    {
+        var classification = EventIngestProcessor.ClassifyEvents(new List<EnrollmentEvent>
+        {
+            Event("script_failed", new Dictionary<string, object> { ["scriptType"] = "platform", ["runId"] = "run-1", ["exitCode"] = "1" }),
+            Event(Constants.EventTypes.ScriptOutputReconciliation, new Dictionary<string, object> { ["scriptType"] = "platform", ["runId"] = "run-1", ["outcome"] = "foreign" }),
+        });
+
+        Assert.True(classification.HasNonPeriodicRealEvent);
+        Assert.Equal(1, classification.PlatformScriptCount);
+    }
+
+    private static EnrollmentEvent Event(string eventType, Dictionary<string, object> data) => new()
+    {
+        EventId = Guid.NewGuid().ToString(),
+        Timestamp = At,
+        EventType = eventType,
+        Source = "RegistryScriptResult",
+        Data = data,
+    };
+}

src/Backend/AutopilotMonitor.Functions.Tests/SessionAnchorSourceTests.cs

@@ -0,0 +1,86 @@
+using System;
+using System.Collections.Generic;
+using AutopilotMonitor.Functions.Services;
+using AutopilotMonitor.Shared;
+using AutopilotMonitor.Shared.Models;
+using Xunit;
+
+namespace AutopilotMonitor.Functions.Tests;
+
+/// <summary>
+/// Backfilled environment observations never set the session start (D-315). Since agent 2.0.1473
+/// the update and servicing watchers deliver rows with their original event time up to 60 min
+/// before the agent started; anchoring on them stretched StartedAt by 22 min at the median
+/// (p90 57 min). Source strings are the persisted wire values, spelled out on purpose.
+/// </summary>
+public class SessionAnchorSourceTests
+{
+    private static readonly DateTime AgentStart = new(2026, 10, 3, 9, 6, 46, DateTimeKind.Utc);
+
+    [Theory]
+    [InlineData("SystemTimelineWatcher")]
+    [InlineData("WindowsUpdateWatcher")]
+    [InlineData("ServicingWatcher")]
+    public void Backfill_sources_are_not_anchor_eligible(string source)
+    {
+        Assert.False(Constants.EventSources.IsSessionAnchorEligible(source));
+    }
+
+    [Theory]
+    [InlineData("ImeLogTracker")]
+    [InlineData("Agent")]
+    [InlineData("MdmRebootPolicyWatcher")]
+    [InlineData("windowsupdatewatcher")] // ordinal: a differently cased source is not the watcher
+    [InlineData(null)]                    // legacy row without a source
+    public void Activity_sources_are_anchor_eligible(string? source)
+    {
+        Assert.True(Constants.EventSources.IsSessionAnchorEligible(source));
+    }
+
+    [Fact]
+    public void Ingest_batch_anchors_on_the_first_activity_not_on_backfilled_update_rows()
+    {
+        // Shape of session 0f1d1f58: update scans and CBS servicing backfilled from before the
+        // IME replay, a clock step even earlier, then IME replay, agent start, a live update row.
+        var firstImeLine = AgentStart.AddMinutes(-10);
+        var liveUpdate = AgentStart.AddMinutes(25);
+        var events = new List<EnrollmentEvent>
+        {
+            Event(AgentStart.AddMinutes(-16), "system_clock_changed", "SystemTimelineWatcher"),
+            Event(AgentStart.AddMinutes(-15), "windows_update_started", "WindowsUpdateWatcher"),
+            Event(AgentStart.AddMinutes(-14), "windows_update_servicing", "ServicingWatcher"),
+            Event(firstImeLine, "ime_agent_version", "ImeLogTracker"),
+            Event(AgentStart, "agent_started", "Agent"),
+            Event(liveUpdate, "windows_update_started", "WindowsUpdateWatcher"),
+        };
+
+        var classification = EventIngestProcessor.ClassifyEvents(events);
+
+        Assert.Equal(firstImeLine, classification.EarliestEventTimestamp);
+        // The latest timestamp still counts every row: a live update row is a real agent report.
+        Assert.Equal(liveUpdate, classification.LatestEventTimestamp);
+    }
+
+    [Fact]
+    public void Ingest_batch_of_only_backfilled_rows_carries_no_anchor()
+    {
+        var events = new List<EnrollmentEvent>
+        {
+            Event(AgentStart.AddMinutes(-50), "windows_update_started", "WindowsUpdateWatcher"),
+            Event(AgentStart.AddMinutes(-40), "windows_update_servicing", "ServicingWatcher"),
+        };
+
+        var classification = EventIngestProcessor.ClassifyEvents(events);
+
+        Assert.Null(classification.EarliestEventTimestamp);
+        Assert.Equal(AgentStart.AddMinutes(-40), classification.LatestEventTimestamp);
+    }
+
+    private static EnrollmentEvent Event(DateTime timestamp, string eventType, string source) => new()
+    {
+        EventId = Guid.NewGuid().ToString(),
+        Timestamp = timestamp,
+        EventType = eventType,
+        Source = source,
+    };
+}

src/Backend/AutopilotMonitor.Functions.Tests/SessionStartedAtBackwardShiftGuardTests.cs

@@ -104,10 +104,14 @@ public class SessionStartedAtBackwardShiftGuardTests
     // =========================== system-timeline rows are not session anchors ====
 
     [Fact]
-    public void IsSessionAnchorEligible_excludes_system_timeline_watcher_rows()
+    public void IsSessionAnchorEligible_excludes_backfilled_environment_rows()
     {
         Assert.False(TableStorageService.IsSessionAnchorEligible(
             new TableEntity("p", "r") { ["Source"] = "SystemTimelineWatcher" }));
+        Assert.False(TableStorageService.IsSessionAnchorEligible(
+            new TableEntity("p", "r") { ["Source"] = "WindowsUpdateWatcher" }));
+        Assert.False(TableStorageService.IsSessionAnchorEligible(
+            new TableEntity("p", "r") { ["Source"] = "ServicingWatcher" }));
         Assert.True(TableStorageService.IsSessionAnchorEligible(
             new TableEntity("p", "r") { ["Source"] = "ImeLogTracker" }));
         Assert.True(TableStorageService.IsSessionAnchorEligible(
@@ -140,6 +144,29 @@ public class SessionStartedAtBackwardShiftGuardTests
         Assert.Equal((int)(lastEvent - firstActivity).TotalSeconds, harness.Written!.GetInt32("DurationSeconds"));
     }
 
+    [Fact]
+    public async Task Pending_duration_skips_backfilled_update_rows_and_anchors_on_activity()
+    {
+        // D-315: update scans and CBS servicing backfilled with their event time up to 60 min
+        // before the agent started were the partition's earliest rows and re-anchored StartedAt.
+        var firstActivity = StartedAt.AddMinutes(-5);
+        var lastEvent = StartedAt.AddMinutes(70);
+        var harness = new Harness(SessionRow(), eventRows: new[]
+        {
+            EventRow(StartedAt.AddMinutes(-55), sequence: 27, source: "WindowsUpdateWatcher"),
+            EventRow(StartedAt.AddMinutes(-50), sequence: 34, source: "ServicingWatcher"),
+            EventRow(firstActivity, sequence: 2, source: "ImeLogTracker"),
+        });
+
+        var ok = await harness.Sut.UpdateSessionStatusAsync(
+            TenantId, SessionId, SessionStatus.Pending, VerdictPaths.AgentWhiteGlovePending,
+            latestEventTimestamp: lastEvent);
+
+        Assert.True(ok);
+        Assert.NotNull(harness.Written);
+        Assert.Equal((int)(lastEvent - firstActivity).TotalSeconds, harness.Written!.GetInt32("DurationSeconds"));
+    }
+
     private static TableEntity EventRow(DateTime occurredUtc, int sequence, string source) =>
         new($"{TenantId}_{SessionId}", $"{occurredUtc:yyyyMMddHHmmssfff}_{sequence:D10}")
         {

src/Backend/AutopilotMonitor.Functions.Tests/SharedManifestParityTests.cs

@@ -90,6 +90,8 @@ public sealed class SharedManifestParityTests
             ["annotationVerdicts"] = AnnotationVerdicts.All,
             // Install channels of the app rows (AppInstallSummary.Source and the per-app DTOs).
             ["appInstallSources"] = AppInstallSources.All,
+            // Event sources whose rows never set a session's start; the portal's session duration applies them.
+            ["sessionAnchorIneligibleSources"] = Constants.EventSources.SessionAnchorIneligible,
             // Community rule submissions: kinds, effective statuses (incl. the derived "published"),
             // attribution modes and reviewer decisions — the MCP tool schemas enumerate these.
             ["ruleSubmissionKinds"] = RuleSubmissionKinds.All,

src/Backend/AutopilotMonitor.Functions/Services/EventIngestProcessor.Classification.cs

@@ -1,4 +1,5 @@
 using AutopilotMonitor.DecisionCore.State;
+using AutopilotMonitor.Shared;
 using AutopilotMonitor.Shared.Models;
 using Microsoft.Extensions.Logging;
 
@@ -9,19 +10,18 @@ namespace AutopilotMonitor.Functions.Services
     /// </summary>
     public sealed partial class EventIngestProcessor
     {
-        private EventClassification ClassifyEvents(List<EnrollmentEvent> storedEvents)
+        internal static EventClassification ClassifyEvents(List<EnrollmentEvent> storedEvents)
         {
             var classification = new EventClassification();
 
             foreach (var evt in storedEvents)
             {
-                // System-timeline-watcher rows (clock steps, sleep episodes) are backfilled
-                // from the Windows event log with original timestamps up to 24h before the
-                // agent started — environment observation, not enrollment activity. They must
-                // not pull the session anchor toward pre-enrollment OOBE idle time (mirrors
-                // TableStorageService.IsSessionAnchorEligible on the Events-table probe;
-                // field case d0c5b672).
-                var anchorEligible = evt.Source != "SystemTimelineWatcher";
+                // Backfilled environment observations (clock steps, sleep, update and servicing
+                // activity from before the agent started) are timeline rows, not enrollment
+                // activity: they must not pull the session anchor into pre-enrollment time
+                // (Constants.EventSources.SessionAnchorIneligible; the Events-table probe applies
+                // the same rule).
+                var anchorEligible = Constants.EventSources.IsSessionAnchorEligible(evt.Source);
                 if (anchorEligible &&
                     (!classification.EarliestEventTimestamp.HasValue || evt.Timestamp < classification.EarliestEventTimestamp.Value))
                     classification.EarliestEventTimestamp = evt.Timestamp;
@@ -480,6 +480,9 @@ namespace AutopilotMonitor.Functions.Services
             // observation too — a device that slept through its stall must stay Stalled.
             "system_clock_changed" => true,
             "system_sleep_episode" => true,
+            // A platform run corrected after the fact from IME's saved result (D-316): registry
+            // observation of an earlier run, not progress — a stalled session stays Stalled.
+            Constants.EventTypes.ScriptOutputReconciliation => true,
             _ => false
         };
 

src/Backend/AutopilotMonitor.Functions/Services/MaintenanceService.Aggregation.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Text;
@@ -795,7 +796,7 @@ namespace AutopilotMonitor.Functions.Services
 
                 var containerClient = new BlobContainerClient(new Uri(containerSasUrl));
                 var generatedAtUtc = DateTime.UtcNow;
-                var versionedFileName = $"platform-stats.{generatedAtUtc:yyyy-MM-dd}.json";
+                var versionedFileName = PlatformStatsVersionedFileName(generatedAtUtc);
 
                 var versionedPayload = new
                 {
@@ -831,19 +832,34 @@ namespace AutopilotMonitor.Functions.Services
             }
         }
 
+        /// <summary>
+        /// Name of the versioned stats file of one publish. The file is served immutable for a year
+        /// (<see cref="PlatformStatsVersionedCacheControl"/>), so a name must never be written twice:
+        /// maintenance publishes every 2 hours, and the per-day name of the once-a-night schedule was
+        /// rewritten up to 12 times a day under that header — caches kept the first copy of the day.
+        /// Browsers revalidate only the manifest, which names the current file.
+        /// </summary>
+        internal static string PlatformStatsVersionedFileName(DateTime generatedAtUtc) =>
+            $"platform-stats.{generatedAtUtc.ToString("yyyy-MM-dd'T'HHmmss'Z'", CultureInfo.InvariantCulture)}.json";
+
         private async Task UploadJsonBlobAsync(BlobContainerClient containerClient, string blobName, object payload, string cacheControl)
         {
             var blobClient = containerClient.GetBlobClient(blobName);
             var json = JsonConvert.SerializeObject(payload);
             await using var stream = new MemoryStream(Encoding.UTF8.GetBytes(json));
 
-            await blobClient.UploadAsync(stream, overwrite: true);
-            await blobClient.SetHttpHeadersAsync(new BlobHttpHeaders
+            // Headers and tier travel with the upload, which still overwrites (the manifest relies on
+            // it). Set in follow-up calls, the blob was briefly served without Cache-Control and
+            // content type, and stayed that way when a follow-up call failed.
+            await blobClient.UploadAsync(stream, new BlobUploadOptions
             {
-                ContentType = "application/json; charset=utf-8",
-                CacheControl = cacheControl
+                HttpHeaders = new BlobHttpHeaders
+                {
+                    ContentType = "application/json; charset=utf-8",
+                    CacheControl = cacheControl
+                },
+                AccessTier = AccessTier.Hot
             });
-            await blobClient.SetAccessTierAsync(AccessTier.Hot);
         }
 
         /// <summary>

src/Backend/AutopilotMonitor.Functions/Services/MaintenanceService.cs

@@ -60,6 +60,7 @@ namespace AutopilotMonitor.Functions.Services
 
         private const string PlatformStatsAliasFileName = "platform-stats.json";
         private const string PlatformStatsAliasCacheControl = "public, max-age=300, stale-while-revalidate=86400";
+        // Holds only because every publish writes a new name (PlatformStatsVersionedFileName).
         private const string PlatformStatsVersionedCacheControl = "public, max-age=31536000, immutable";
 
         public MaintenanceService(

src/Backend/AutopilotMonitor.Functions/Services/TableStorageService.Sessions.cs

@@ -3540,18 +3540,15 @@ namespace AutopilotMonitor.Functions.Services
         }
 
         /// <summary>
-        /// Event sources whose rows never anchor the session. The system timeline watcher
-        /// backfills environment observations (clock steps, sleep episodes) from the Windows
-        /// event log with their ORIGINAL timestamps — up to 24h before the agent started.
-        /// They belong on the timeline, but they are not enrollment activity: anchoring on
-        /// them silently stretches StartedAt/DurationSeconds toward pre-enrollment OOBE idle
-        /// time (field case d0c5b672: a pre-agent clock correction pulled StartedAt ~14min
-        /// before the first real activity; the 2h backward-shift guard only caps, not
-        /// prevents, this). User decision 2026-08-21: the session anchor stays on real
-        /// enrollment activity.
+        /// Whether an event row may anchor the session (<see cref="Constants.EventSources.SessionAnchorIneligible"/>).
+        /// Backfilled environment observations carry their ORIGINAL event time, up to 24h before
+        /// the agent started; anchoring on them silently stretches StartedAt/DurationSeconds into
+        /// pre-enrollment time (field case d0c5b672: a pre-agent clock correction, ~14 min; the 2h
+        /// backward-shift guard only caps this). User decision 2026-08-21: the session anchor
+        /// stays on real enrollment activity.
         /// </summary>
         internal static bool IsSessionAnchorEligible(TableEntity eventRow)
-            => eventRow.GetString("Source") != "SystemTimelineWatcher";
+            => Constants.EventSources.IsSessionAnchorEligible(eventRow.GetString("Source"));
 
         /// <summary>
         /// Returns the earliest ANCHOR-ELIGIBLE event timestamp persisted for a session, if

src/McpServer/autopilot-monitor-mcp/src/__tests__/script-output-correction.test.ts

@@ -0,0 +1,95 @@
+/**
+ * D-316: a platform run whose script_failed came from another script's end block is corrected by a later
+ * script_output_reconciliation (outcome "foreign", IME result Success). get_session_summary must not count the
+ * stored script_failed as an error, must not rank it as one and must not attach the foreign exit code's catalog
+ * text; the correction itself stays a Warning key event.
+ *
+ * Pure unit tests: fetch is stubbed and the registered tool handler is invoked directly.
+ */
+import { describe, it, expect, vi, afterEach } from 'vitest';
+import { McpServer } from '@modelcontextprotocol/server';
+import { registerTools } from '../tools.js';
+import { runWithCaller } from '../client.js';
+import { foreignSuccessRunIds, isCorrectedForeignFailure } from '../tools/shared.js';
+
+type ToolHandler = (args: Record<string, unknown>, extra: unknown) => Promise<{ content?: Array<{ type: string; text?: string }> }>;
+
+const SESSION = 'e259c121-1234-4abc-9def-0123456789ab';
+const GA = { token: 'ga', isGlobalAdmin: true };
+const extra = { signal: new AbortController().signal };
+
+function summaryHandler(): ToolHandler {
+  const server = new McpServer({ name: 'test', version: '0.0.0' });
+  registerTools(server, undefined, undefined, undefined, true, true, false);
+  const registry = (server as unknown as { _registeredTools: Record<string, { handler: ToolHandler }> })._registeredTools;
+  return registry['get_session_summary'].handler;
+}
+
+function stubBackend(events: unknown[]): void {
+  const body = {
+    success: true,
+    session: { sessionId: SESSION, tenantId: 't', status: 'Succeeded', startedAt: '2026-10-03T20:49:00Z' },
+    events,
+    results: [],
+    annotations: [],
+    count: events.length,
+  };
+  vi.stubGlobal('fetch', vi.fn(async () => ({ ok: true, status: 200, json: async () => body, text: async () => JSON.stringify(body) }) as unknown as Response));
+}
+
+afterEach(() => vi.unstubAllGlobals());
+
+const foreignFailure = {
+  timestamp: '2026-10-03T20:59:04Z',
+  eventType: 'script_failed',
+  severity: 'Error',
+  source: 'ImeLogTracker',
+  message: 'Platform script d94468af: Success (exit: 1)',
+  data: { scriptType: 'platform', result: 'Success', exitCode: '1', runId: 'run-1' },
+};
+
+const correction = (data: Record<string, unknown>) => ({
+  timestamp: '2026-10-03T20:59:08Z',
+  eventType: 'script_output_reconciliation',
+  severity: 'Warning',
+  source: 'RegistryScriptResult',
+  message: "Platform script d94468af: output corrected from IME's saved result",
+  data: { scriptType: 'platform', outcome: 'foreign', result: 'Success', runId: 'run-1', ...data },
+});
+
+async function summary(events: unknown[]): Promise<Record<string, any>> {
+  stubBackend(events);
+  const result = await runWithCaller(GA, () => summaryHandler()({ sessionId: SESSION }, extra));
+  return JSON.parse((result.content ?? []).map((c) => c.text ?? '').join(''));
+}
+
+describe('get_session_summary with a corrected platform run', () => {
+  it('does not count the foreign script_failed as an error and drops its exit-code text', async () => {
+    const body = await summary([foreignFailure, correction({})]);
+
+    expect(body.stats.errorCount).toBe(0);
+    expect(body.stats.warningCount).toBe(1);
+    const failed = body.keyEvents.find((e: { eventType: string }) => e.eventType === 'script_failed');
+    expect(failed.correctedByImeSavedResult).toBe(true);
+    expect(failed.errorCode).toBeUndefined();
+    expect(body.keyEvents.some((e: { eventType: string }) => e.eventType === 'script_output_reconciliation')).toBe(true);
+  });
+
+  it('keeps counting a failure IME itself reported, and an uncorrected one', async () => {
+    expect((await summary([foreignFailure, correction({ result: 'Failed' })])).stats.errorCount).toBe(1);
+    expect((await summary([foreignFailure, correction({ outcome: 'repaired' })])).stats.errorCount).toBe(1);
+    expect((await summary([foreignFailure, correction({ runId: 'another-run' })])).stats.errorCount).toBe(1);
+    expect((await summary([foreignFailure])).stats.errorCount).toBe(1);
+  });
+});
+
+describe('foreignSuccessRunIds / isCorrectedForeignFailure', () => {
+  it('names only foreign corrections whose IME result is Success, and only script_failed rows', () => {
+    const runs = foreignSuccessRunIds([correction({}), correction({ runId: 'r2', result: 'Failed' }), correction({ runId: 'r3', outcome: 'repaired' })]);
+    expect([...runs]).toEqual(['run-1']);
+    expect(isCorrectedForeignFailure('script_failed', { runId: 'run-1' }, runs)).toBe(true);
+    expect(isCorrectedForeignFailure('script_completed', { runId: 'run-1' }, runs)).toBe(false);
+    expect(isCorrectedForeignFailure('script_failed', { runId: 'r2' }, runs)).toBe(false);
+    expect(isCorrectedForeignFailure('script_failed', undefined, runs)).toBe(false);
+  });
+});

src/McpServer/autopilot-monitor-mcp/src/resource-catalog.ts

@@ -96,7 +96,7 @@ export const EVENT_TYPES_CATALOG = {
     'office_install_failed',
     'office_preinstalled_detected',
   ],
-  script_events: ['script_started', 'script_completed', 'script_failed', 'script_timeout_suspected', 'script_recurrence_summary', 'historic_ime_replay_detected'],
+  script_events: ['script_started', 'script_completed', 'script_failed', 'script_output_reconciliation', 'script_timeout_suspected', 'script_recurrence_summary', 'historic_ime_replay_detected'],
   network_events: [
     'network_state_change',
     'network_connectivity_check',

src/McpServer/autopilot-monitor-mcp/src/tools/sessions.ts

@@ -2,7 +2,7 @@ import { McpServer } from '@modelcontextprotocol/server';
 import { z } from 'zod';
 import { ApiError, apiFetch, buildQuery, jsonBody, DEFAULT_FIRST_PAGE_SIZE, effectivePageSize, enforceDelegatedTenant, enforceDelegatedTenantForPage, followNextLink, pageSizeForCall, pickGlobalOrTenantPath, scanUntilMatch, scanWithTimeoutFallback } from '../client.js';
 import { withToolTelemetry } from '../telemetry.js';
-import { READ_ONLY, MAX_RESULT_SIZE_CHARS, LEAN_EVENT_FIELDS, LEAN_EVENT_OMISSION, leanFieldSelection, SUMMARY_EVENT_FIELDS, toolResultText, SessionIdSchema, isBenignHealthDetectionReport, tenantIdDescription, pageSizeDescription, CONTINUATION_DESCRIPTION, daysDescription } from './shared.js';
+import { READ_ONLY, MAX_RESULT_SIZE_CHARS, LEAN_EVENT_FIELDS, LEAN_EVENT_OMISSION, leanFieldSelection, SUMMARY_EVENT_FIELDS, toolResultText, SessionIdSchema, isBenignHealthDetectionReport, foreignSuccessRunIds, isCorrectedForeignFailure, tenantIdDescription, pageSizeDescription, CONTINUATION_DESCRIPTION, daysDescription } from './shared.js';
 import { toolError } from './error-handler.js';
 import { lookupErrorCode } from '../error-code-catalog.js';
 import { withEventTypeNote, assertKnownDevicePropertyKeys } from '../resource-catalog.js';
@@ -534,6 +534,8 @@ export function registerSessionTools(server: McpServer, ga: boolean, delegated:
         // Observation coverage: what the agent could and could not see, folded from the
         // health/lifecycle events that the triage timeline below ranks low or drops.
         const coverage = buildSessionCoverage(s, allEvents);
+        // Platform runs IME's saved result proved to carry another script's exit code (D-316).
+        const foreignRuns = foreignSuccessRunIds(allEvents);
 
         let errorCount = 0;
         let warningCount = 0;
@@ -545,7 +547,8 @@ export function registerSessionTools(server: McpServer, ga: boolean, delegated:
           const sev = String(e.severity ?? '');
           // A compliant health-script detection mis-stamped script_failed/Error is benign —
           // exclude it so a green session's errorCount isn't inflated by routine compliance reports.
-          const benign = isBenignHealthDetectionReport(String(e.eventType ?? ''), e.data);
+          const benign = isBenignHealthDetectionReport(String(e.eventType ?? ''), e.data)
+            || isCorrectedForeignFailure(String(e.eventType ?? ''), e.data, foreignRuns);
           if (!benign && (sev === 'Error' || sev === 'Critical')) errorCount++;
           if (sev === 'Warning') warningCount++;
           const et = String(e.eventType ?? '');
@@ -571,6 +574,8 @@ export function registerSessionTools(server: McpServer, ga: boolean, delegated:
         const relevanceScore = (e: Partial<EnrollmentEvent>): number => {
           // Benign compliant detection mis-stamped Error → rank as info-level, not top.
           if (isBenignHealthDetectionReport(String(e.eventType ?? ''), e.data)) return 10;
+          // A failure that was another script's exit code is not a failure of this one.
+          if (isCorrectedForeignFailure(String(e.eventType ?? ''), e.data, foreignRuns)) return 10;
           const sev = SEVERITY_RANK[String(e.severity ?? '')] ?? -1;
           if (sev >= 3) return 100;                        // Error/Critical
           if (PHASE_EVENT_TYPES.has(String(e.eventType ?? ''))) return 60;
@@ -597,7 +602,10 @@ export function registerSessionTools(server: McpServer, ga: boolean, delegated:
           phase: phaseName(e.phase, s.enrollmentType),
           message: e.message,
           source: e.source,
-          ...keyEventErrorCode(e.data, e.source),
+          // The exit code on a corrected run was another script's: no catalog text for it.
+          ...(isCorrectedForeignFailure(String(e.eventType ?? ''), e.data, foreignRuns)
+            ? { correctedByImeSavedResult: true }
+            : keyEventErrorCode(e.data, e.source)),
         }));
 
         let analysis = null;

src/McpServer/autopilot-monitor-mcp/src/tools/shared.ts

@@ -75,6 +75,8 @@ export function leanFieldSelection(
 export const SUMMARY_EVENT_FIELDS =
   'eventType,severity,source,phase,timestamp,message,sequence,' +
   'data.scriptType,data.script_type,data.scriptPart,data.script_part,data.result,' +
+  // Platform-run corrections from IME's saved result (foreignSuccessRunIds below).
+  'data.runId,data.outcome,' +
   'data.rejectedSourceTimestamp,data.rejected_source_timestamp,' +
   'data.errorCode,data.exitCode,data.hresult,data.hresultFromWin32,data.hresultSymbol,' +
   'data.errorCodeInfo,data.exitCodeInfo,data.hresultInfo,data.hresultFromWin32Info,' +
@@ -125,6 +127,38 @@ export function isBenignHealthDetectionReport(
   return true;
 }
 
+/**
+ * Run ids of platform runs whose `script_failed` came from another script's end block while IME
+ * itself reported Success: `script_output_reconciliation` with outcome "foreign" and result Success
+ * (D-316 — the agent had attributed a foreign executor's exit code and output; IME's saved result
+ * proved it). The stored `script_failed` stays as written; read sides treat it like the benign
+ * detection reports above: no error count, info-level rank, no exit-code catalog text.
+ */
+export function foreignSuccessRunIds(
+  events: ReadonlyArray<{ eventType?: string | null; data?: Record<string, unknown> }>,
+): Set<string> {
+  const runs = new Set<string>();
+  for (const e of events) {
+    if (e.eventType !== 'script_output_reconciliation' || !e.data) continue;
+    if (String(e.data.outcome ?? '') !== 'foreign') continue;
+    if (String(e.data.result ?? '').toLowerCase() !== 'success') continue;
+    const runId = e.data.runId;
+    if (typeof runId === 'string' && runId.length > 0) runs.add(runId);
+  }
+  return runs;
+}
+
+/** True for a `script_failed` whose run `foreignSuccessRunIds` names. */
+export function isCorrectedForeignFailure(
+  eventType: string | undefined,
+  data: Record<string, unknown> | undefined,
+  foreignRuns: ReadonlySet<string>,
+): boolean {
+  if (eventType !== 'script_failed' || !data || foreignRuns.size === 0) return false;
+  const runId = data.runId;
+  return typeof runId === 'string' && foreignRuns.has(runId);
+}
+
 /**
  * Builds the role-aware description for a tenant-boundable tool's `tenantId` argument. MCP clients weigh
  * the per-arg schema heavily, so a delegated (MSP) caller — for whom omitting tenantId is REJECTED, not

src/Shared/AutopilotMonitor.Shared/Constants.cs

@@ -543,6 +543,13 @@ namespace AutopilotMonitor.Shared
             // policies on its own schedule for as long as the device is up; the first run and
             // every run with a different result are still emitted in full.
             public const string ScriptRecurrenceSummary = "script_recurrence_summary";
+            // A platform script's emitted output disagreed with IME's own saved result
+            // (HKLM\...\IntuneManagementExtension\Policies\<user>\<policy>, written after IME reported the
+            // script batch): Data.outcome "foreign" (Warning, immediate upload — the run had been given
+            // another executor's end block; Data.stdout/stderr replace it, the exit code is unverified) or
+            // "repaired" (Info — the log had delivered the output incomplete). Data.runId names the corrected
+            // script_completed/script_failed. Observability only, never DecisionEngine input.
+            public const string ScriptOutputReconciliation = "script_output_reconciliation";
             // One-shot per agent run: the IME adapter detected replayed log content from a
             // previous enrollment (source lines > 24 h stale, e.g. IME logs surviving a
             // re-enrollment) and suppressed the historic script (script_started/completed/
@@ -913,6 +920,37 @@ namespace AutopilotMonitor.Shared
             /// author-defined (no error-code enrichment unless <see cref="GatherRuleDataKeys.EnrichErrorCodes"/>).
             /// </summary>
             public const string GatherRuleExecutor = "GatherRuleExecutor";
+
+            /// <summary>Clock steps and sleep episodes from the Windows System log.</summary>
+            public const string SystemTimelineWatcher = "SystemTimelineWatcher";
+
+            /// <summary>Windows Update client events (System and Operational log).</summary>
+            public const string WindowsUpdateWatcher = "WindowsUpdateWatcher";
+
+            /// <summary>CBS servicing steps from the Setup log.</summary>
+            public const string ServicingWatcher = "ServicingWatcher";
+
+            /// <summary>
+            /// Sources whose rows never set a session's start. Their watchers backfill the Windows
+            /// event logs with the original event time — clock steps and sleep up to 24 h, update
+            /// and servicing activity up to 60 min before the agent started — so their earliest row
+            /// is environment observation from before the enrollment, not its first step. Every
+            /// place that derives the start from events applies this list: backend ingest and the
+            /// Events-table probe, and the portal's session duration via shared-manifests.json.
+            /// </summary>
+            public static readonly string[] SessionAnchorIneligible =
+            {
+                SystemTimelineWatcher,
+                WindowsUpdateWatcher,
+                ServicingWatcher,
+            };
+
+            /// <summary>
+            /// False for <see cref="SessionAnchorIneligible"/> sources; true otherwise, including a
+            /// row without a source.
+            /// </summary>
+            public static bool IsSessionAnchorEligible(string? source) =>
+                System.Array.IndexOf(SessionAnchorIneligible, source) < 0;
         }
 
         /// <summary>

src/Web/autopilot-monitor-web/app/admin/components/TenantAdminSection.tsx

@@ -170,44 +170,37 @@ export function TenantAdminSection({
   };
 
   return (
-    <div className="bg-purple-50 border border-purple-200 rounded-lg p-4">
-      <div className="flex items-start space-x-3">
-        <svg className="w-5 h-5 text-purple-600 mt-0.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-          <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 4.354a4 4 0 110 5.292M15 21H3v-1a6 6 0 0112 0v1zm0 0h6v-1a6 6 0 00-9-5.197M13 7a4 4 0 11-8 0 4 4 0 018 0z" />
-        </svg>
-        <div className="flex-1 min-w-0 space-y-4">
-          <p className="font-semibold text-purple-900">
-            Members
-            {loadingAdmins && <span className="ml-2 text-sm font-normal text-purple-700">(Loading...)</span>}
-          </p>
+    <div className="bg-purple-50 border border-purple-200 rounded-lg p-4 space-y-4">
+      <h3 className="font-semibold text-purple-900">
+        Members
+        {loadingAdmins && <span className="ml-2 text-sm font-normal text-purple-700">(Loading...)</span>}
+      </h3>
 
-          <AddMemberForm
-            value={newAdminEmail}
-            onValueChange={setNewAdminEmail}
-            role={newMemberRole}
-            onRoleChange={setNewMemberRole}
-            kind={newMemberKind}
-            onKindChange={setNewMemberKind}
-            adding={addingAdmin}
-            onAdd={handleAddTenantAdmin}
-            disabled={!canMutate}
-            stacked
-          />
+      <AddMemberForm
+        value={newAdminEmail}
+        onValueChange={setNewAdminEmail}
+        role={newMemberRole}
+        onRoleChange={setNewMemberRole}
+        kind={newMemberKind}
+        onKindChange={setNewMemberKind}
+        adding={addingAdmin}
+        onAdd={handleAddTenantAdmin}
+        disabled={!canMutate}
+        stacked
+      />
 
-          {/* key: a tenant switch starts on page 1 with no filter, search or open row. */}
-          <MemberList
-            key={tenantId}
-            members={tenantAdmins}
-            loading={loadingAdmins}
-            canMutate={canMutate}
-            removingUpn={removingAdmin}
-            updatingUpn={togglingAdmin}
-            onRemove={handleRemoveTenantAdmin}
-            onToggleEnabled={handleToggleTenantAdmin}
-            onUpdatePermissions={handleUpdatePermissions}
-          />
-        </div>
-      </div>
+      {/* key: a tenant switch starts on page 1 with no filter, search or open row. */}
+      <MemberList
+        key={tenantId}
+        members={tenantAdmins}
+        loading={loadingAdmins}
+        canMutate={canMutate}
+        removingUpn={removingAdmin}
+        updatingUpn={togglingAdmin}
+        onRemove={handleRemoveTenantAdmin}
+        onToggleEnabled={handleToggleTenantAdmin}
+        onUpdatePermissions={handleUpdatePermissions}
+      />
     </div>
   );
 }

src/Web/autopilot-monitor-web/app/gather-rules/eventTypes.ts

@@ -152,6 +152,8 @@ export const KNOWN_EVENT_TYPES: EventTypeEntry[] = [
     description: "A platform script completed, or one phase (detection / remediation / post-detection) of a health script completed. Health scripts emit up to three of these per policy run." },
   { value: "script_failed", label: "script_failed", category: "script",
     description: "A platform script crashed (exit code != 0), or the remediation phase of a health script crashed. Health-script detection / post-detection phases use exit code as a compliance verdict (non-zero = non-compliant) and emit script_completed even on non-zero exit; only a true script crash in those phases would surface here." },
+  { value: "script_output_reconciliation", label: "script_output_reconciliation", category: "script",
+    description: "A platform script's reported output disagreed with the result IME saved after reporting the script batch. Outcome \"foreign\" (Warning): the run had been given another script's output and exit code; the saved output replaces it and the exit code is unknown. Outcome \"repaired\" (Info): the output had arrived incomplete. Carries runId (the corrected run), policyId, outcome, reason, result, stdout and stderr." },
   { value: "script_timeout_suspected", label: "script_timeout_suspected", category: "script",
     description: "A platform script ran to the IME script-execution timeout (~30 min; threshold 25 min) and was marked Failed while the enrollment was in progress. IME runs platform scripts serially, so a hung script starves app installs and the Autopilot-Monitor bootstrap — the prime suspect behind a late agent start / pre-failed ESP. Advisory (one per policyId); carries durationSeconds, exitCode and espPhase." },
   { value: "script_recurrence_summary", label: "script_recurrence_summary", category: "script",

src/Web/autopilot-monitor-web/app/page.tsx

@@ -1,41 +1,17 @@
-import { AuthGate } from "../components/landing/AuthGate";
-import { LandingNavbar } from "../components/landing/LandingNavbar";
-import { Hero } from "../components/landing/Hero";
-import { StatsBand } from "../components/landing/StatsBand";
-import { JustAsk } from "../components/landing/JustAsk";
-import { Story } from "../components/landing/Story";
-import { CapabilitiesStrip } from "../components/landing/CapabilitiesStrip";
-import { Comparison } from "../components/landing/Comparison";
-import { HowItWorks } from "../components/landing/HowItWorks";
-import { Testimonials } from "../components/landing/Testimonials";
-import { FinalCta } from "../components/landing/FinalCta";
-import { SiteFooter } from "../components/SiteFooter";
-import { MarketingTracker } from "../components/MarketingTracker";
+import { LandingPage } from "../components/landing/LandingPage";
+import { loadPlatformStatsSnapshot } from "../lib/platformStats";
+
+// The stats read below runs once per `next build` and bypasses Next's fetch cache (`no-store`,
+// see lib/platformStats.ts). force-static keeps that legal in the static export; the landing
+// tree reads no request-time API (cookies, headers, search params) that it would blank out.
+export const dynamic = "force-static";
 
 /**
- * Landing page v2 — a scroll story of one enrollment.
- * All theming goes through the lp-* tokens (globals.css); sections live
- * in components/landing/. Auth behavior (AuthGate redirect, LoginButton
- * portal handoff) is unchanged from v1.
+ * The landing page with the platform stats of the build baked into its static HTML, so
+ * crawlers and LLM fetchers that run no JS see the numbers too; browsers then load the live
+ * ones (components/landing/StatsBand.tsx). Awaited here, not under a Suspense boundary: React
+ * would move a resolved boundary of a page this size into a hidden div at the end of the body.
  */
-export default function LandingPage() {
-  return (
-    <div className="landing-v2 min-h-screen bg-[var(--lp-bg)]">
-      {/* Client component: handles auth redirect + loading overlay */}
-      <AuthGate />
-      <MarketingTracker page="landing">
-        <LandingNavbar />
-        <Hero />
-        <StatsBand />
-        <JustAsk />
-        <Story />
-        <CapabilitiesStrip />
-        <Comparison />
-        <HowItWorks />
-        <Testimonials />
-        <FinalCta />
-        <SiteFooter />
-      </MarketingTracker>
-    </div>
-  );
+export default async function Page() {
+  return <LandingPage statsSnapshot={await loadPlatformStatsSnapshot()} />;
 }

src/Web/autopilot-monitor-web/app/sessions/components/EventTimeline.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { useState, useMemo, useDeferredValue } from "react";
+import { createContext, useContext, useState, useMemo, useDeferredValue } from "react";
 import { EnrollmentEvent, Session } from "@/types";
 import { normalizeEventDataForDisplay, shortenBuildHashInMessage } from "../utils/eventHelpers";
 import { buildEventSearchMatcher, formatEventSearchTerm, parseEventSearchQuery } from "../utils/eventSearchQuery";
@@ -8,6 +8,11 @@ import { getEnrichedOrLookup, formatErrorCode, errorCodeTooltip, type ErrorCodeI
 import { readTimeProvenance, classifyTimeJump, readClockChangeDeltaMs } from "@/lib/timeProvenance";
 import { isRebootOrRetryClass } from "@/lib/installProgress";
 import { formatDuration, formatUtcOffset } from "@/lib/formatting";
+import { SCRIPT_OUTPUT_RECONCILIATION } from "@/lib/scriptExecutions";
+
+// runId → outcome of every platform run that IME's saved result corrected later (D-316): the
+// run's own row says so, so its emitted output is never read as the script's.
+const CorrectedRunsContext = createContext<ReadonlyMap<string, "foreign" | "repaired">>(new Map());
 
 const SEARCH_SYNTAX_HINT =
   "Searches event type, message, source and the details JSON (e.g. gather output). " +
@@ -104,10 +109,20 @@ export default function EventTimeline({
     [events],
   );
 
+  const correctedRuns = useMemo(() => {
+    const runs = new Map<string, "foreign" | "repaired">();
+    for (const e of events) {
+      if (e.eventType !== SCRIPT_OUTPUT_RECONCILIATION) continue;
+      const runId = e.data?.runId;
+      if (typeof runId === "string" && runId.length > 0) runs.set(runId, e.data?.outcome === "foreign" ? "foreign" : "repaired");
+    }
+    return runs;
+  }, [events]);
+
   const filterPhaseEvents = (phaseEvents: EnrollmentEvent[]) =>
     matchesSearch ? phaseEvents.filter(matchesSearch) : phaseEvents;
 
-  return (
+  const timeline = (
     <div className="space-y-6">
       {/* Search + Severity filters + Expand/Collapse — shared controls above the timeline(s) */}
       <div className="flex flex-col sm:flex-row sm:items-center gap-2">
@@ -356,6 +371,8 @@ export default function EventTimeline({
       )}
     </div>
   );
+
+  return <CorrectedRunsContext.Provider value={correctedRuns}>{timeline}</CorrectedRunsContext.Provider>;
 }
 
 function PhaseSection({
@@ -515,7 +532,13 @@ function EventRow({ event, showScriptOutput, prevEvent, clockDeltas }: { event:
   // timeline still applies the same script-event styling/iconography.
   const isScriptEvent = event.eventType === "script_started"
     || event.eventType === "script_completed"
-    || event.eventType === "script_failed";
+    || event.eventType === "script_failed"
+    || event.eventType === SCRIPT_OUTPUT_RECONCILIATION;
+  const correctedRuns = useContext(CorrectedRunsContext);
+  const eventRunId = event.data?.runId;
+  const laterCorrection = event.eventType !== SCRIPT_OUTPUT_RECONCILIATION && typeof eventRunId === "string"
+    ? correctedRuns.get(eventRunId)
+    : undefined;
   const detailData = useMemo(() => {
     if (!rawDetailData || !isScriptEvent || showScriptOutput !== false) return rawDetailData;
     const filtered = { ...rawDetailData };
@@ -611,6 +634,13 @@ function EventRow({ event, showScriptOutput, prevEvent, clockDeltas }: { event:
             <span className="text-sm font-medium text-gray-900">{event.eventType}</span>
           </div>
           <p className="mt-1 text-sm text-gray-600" title={event.message || undefined}>{shortenBuildHashInMessage(event.message)}</p>
+          {laterCorrection && (
+            <p className="mt-0.5 text-xs text-gray-500">
+              {laterCorrection === "foreign"
+                ? "Corrected later from IME's saved result: the output and exit code on this row belonged to another script."
+                : "Output completed later from IME's saved result."}
+            </p>
+          )}
           {/* Exit code / HRESULT badge for app install events */}
           {(event.eventType === "app_install_failed" || event.eventType === "app_install_completed") && (() => {
             const ec = (event.data?.exitCode ?? event.data?.exit_code) as string | number | undefined;

src/Web/autopilot-monitor-web/app/sessions/page.tsx

@@ -234,6 +234,8 @@ function SessionDetailContent() {
       e => e.eventType === "script_started"
         || e.eventType === "script_completed"
         || e.eventType === "script_failed"
+        // Corrections of a platform run from IME's saved result (D-316) — applied by the reducer.
+        || e.eventType === "script_output_reconciliation"
     ),
     [events]
   );

src/Web/autopilot-monitor-web/components/ScriptExecutions.tsx

@@ -30,6 +30,14 @@ import PhaseDivider from "@/components/PhaseDivider";
 // span is hours of offset error rather than run time (a 10 s script once read "1h 00m").
 const DURATION_SUPPRESSED_TITLE = "Run time not measurable: the start and end log lines were resolved on different timezone assumptions, so their span would be offset error, not run time";
 
+// IME's saved result corrected the run (script_output_reconciliation): the log had attributed
+// another script's end block to it, so its exit code is unknown and the output shown is IME's.
+const EXIT_UNVERIFIED_TITLE = "Exit code unknown: the IME log had attributed another script's output and exit code to this run. The output shown is this script's own, as IME saved it.";
+const OUTPUT_CORRECTED_TITLE: Record<"foreign" | "repaired", string> = {
+  foreign: "The IME log had attributed another script's output to this run. This is the script's own output, as IME saved it after reporting the result.",
+  repaired: "The IME log delivered this output incomplete. This is the full output, as IME saved it after reporting the result.",
+};
+
 interface ScriptExecutionsProps {
   events: ScriptInputEvent[];
   showScriptOutput?: boolean;
@@ -528,6 +536,9 @@ function ScriptItemRow({ item, showScriptOutput, latestBootstrapVersion, nested,
               exit {item.exitCode}
             </span>
           )}
+          {item.exitCode == null && item.outputCorrection === "foreign" && (
+            <span className="font-mono text-gray-400" title={EXIT_UNVERIFIED_TITLE}>exit n/a</span>
+          )}
           {durationLabel && (
             <span
               className={`font-mono ${isSlowDuration ? "text-amber-600 font-medium" : "text-gray-500"}`}
@@ -564,6 +575,9 @@ function ScriptItemRow({ item, showScriptOutput, latestBootstrapVersion, nested,
             {!nested && item.runContext && <span><span className="font-medium text-gray-700">Context:</span> {item.runContext}</span>}
             {!nested && item.targetType != null && <span><span className="font-medium text-gray-700">Target:</span> {item.targetType === 2 ? "Device" : "User"}</span>}
             {item.exitCode != null && <span><span className="font-medium text-gray-700">Exit Code:</span> <span className="font-mono">{item.exitCode}</span></span>}
+            {item.exitCode == null && item.outputCorrection === "foreign" && (
+              <span title={EXIT_UNVERIFIED_TITLE}><span className="font-medium text-gray-700">Exit Code:</span> <span className="font-mono text-gray-400">n/a</span></span>
+            )}
             {detailDurationLabel && <span><span className="font-medium text-gray-700">Duration:</span> <span className={`font-mono ${isSlowDuration ? "text-amber-600" : ""}`}>{detailDurationLabel}</span></span>}
             {!detailDurationLabel && item.durationSuppressedReason && (
               <span title={DURATION_SUPPRESSED_TITLE}><span className="font-medium text-gray-700">Duration:</span> <span className="font-mono text-gray-400">n/a</span></span>
@@ -601,7 +615,12 @@ function ScriptItemRow({ item, showScriptOutput, latestBootstrapVersion, nested,
 
           {hasStdout && (
             <div>
-              <div className="text-xs font-medium text-gray-500 mb-1">stdout</div>
+              <div className="text-xs font-medium text-gray-500 mb-1">
+                stdout
+                {item.outputCorrection && (
+                  <span className="font-normal text-gray-400" title={OUTPUT_CORRECTED_TITLE[item.outputCorrection]}>{" · from IME's saved result"}</span>
+                )}
+              </div>
               <div className="p-2 bg-gray-900 rounded text-xs text-gray-100 font-mono overflow-x-auto max-h-48 overflow-y-auto">
                 <pre className="whitespace-pre-wrap break-words">{item.stdout}</pre>
               </div>
@@ -614,7 +633,12 @@ function ScriptItemRow({ item, showScriptOutput, latestBootstrapVersion, nested,
 
           {hasStderr && (
             <div>
-              <div className="text-xs font-medium text-red-500 mb-1">stderr</div>
+              <div className="text-xs font-medium text-red-500 mb-1">
+                stderr
+                {item.outputCorrection && (
+                  <span className="font-normal text-gray-400" title={OUTPUT_CORRECTED_TITLE[item.outputCorrection]}>{" · from IME's saved result"}</span>
+                )}
+              </div>
               <div className="p-2 bg-gray-900 rounded text-xs text-red-300 font-mono overflow-x-auto max-h-48 overflow-y-auto">
                 <pre className="whitespace-pre-wrap break-words">{item.stderr}</pre>
               </div>

src/Web/autopilot-monitor-web/components/__tests__/landingStats.test.ts

@@ -0,0 +1,67 @@
+import { describe, it, expect, vi } from "vitest";
+import { createElement } from "react";
+import { renderToStaticMarkup } from "react-dom/server";
+import { prerender } from "react-dom/static";
+
+// LandingNavbar and LoginButton read the auth context; the public pages render signed out.
+vi.mock("@/contexts/AuthContext", () => ({
+  useAuth: () => ({ login: async () => undefined, isAuthenticated: false, user: null, getAccessToken: async () => null }),
+}));
+// AuthGate only redirects signed-in visitors (it needs the app router) and renders no links.
+vi.mock("@/components/landing/AuthGate", () => ({ AuthGate: () => null }));
+
+const { SNAPSHOT } = vi.hoisted(() => ({
+  SNAPSHOT: {
+    items: [
+      { label: "enrollments monitored", value: "12,481" },
+      { label: "events processed", value: "8.3M" },
+    ],
+    asOf: "2026-10-02T14:00:03.1234567Z",
+  },
+}));
+// The blob read itself is covered in lib/__tests__/platformStats.test.ts.
+vi.mock("@/lib/platformStats", async importOriginal => ({
+  ...(await importOriginal<typeof import("@/lib/platformStats")>()),
+  loadPlatformStatsSnapshot: async () => SNAPSHOT,
+}));
+
+import LandingRoute from "@/app/page";
+import { StatsBand } from "@/components/landing/StatsBand";
+
+/**
+ * Crawlers and LLM fetchers run no JS: the platform stats only reach them when the build renders
+ * the numbers into the landing page's HTML (lib/platformStats.ts, app/page.tsx).
+ */
+describe("platform stats in the landing page's static HTML", () => {
+  it("the band renders the baked numbers and marks the snapshot", () => {
+    const html = renderToStaticMarkup(createElement(StatsBand, { snapshot: SNAPSHOT }));
+    expect(html).toContain(">12,481<");
+    expect(html).toContain(">enrollments monitored<");
+    expect(html).toContain(">8.3M<");
+    expect(html).toContain(`data-stats-snapshot="${SNAPSHOT.asOf}"`);
+    expect(html).not.toContain("animate-pulse");
+  });
+
+  it("without a snapshot the band shows the loading skeleton and no marker", () => {
+    const html = renderToStaticMarkup(createElement(StatsBand, { snapshot: null }));
+    expect(html).toContain('data-track-section="stats"');
+    expect(html).toContain("animate-pulse");
+    expect(html).not.toContain("data-stats-snapshot");
+  });
+
+  // A Suspense boundary around the read would still resolve at build time, but React moves a
+  // resolved boundary of a page this size into a hidden div at the end of the body.
+  it("the page renders the numbers in place, not in a hidden streaming segment", async () => {
+    const { prelude } = await prerender(createElement(LandingRoute));
+    const html = await new Response(prelude).text();
+
+    const bandStart = html.indexOf('data-track-section="stats"');
+    const nextSection = html.indexOf('data-track-section="just_ask"');
+    const figure = html.indexOf(">12,481<");
+    expect(bandStart).toBeGreaterThan(-1);
+    expect(figure).toBeGreaterThan(bandStart);
+    expect(figure).toBeLessThan(nextSection);
+    expect(html).toContain(`data-stats-snapshot="${SNAPSHOT.asOf}"`);
+    expect(html).not.toMatch(/<div hidden id="S:/);
+  });
+});

src/Web/autopilot-monitor-web/components/__tests__/marketingLinks.guard.test.ts

@@ -9,7 +9,7 @@ vi.mock("@/contexts/AuthContext", () => ({
 // AuthGate only redirects signed-in visitors (it needs the app router) and renders no links.
 vi.mock("@/components/landing/AuthGate", () => ({ AuthGate: () => null }));
 
-import LandingPage from "@/app/page";
+import { LandingPage } from "@/components/landing/LandingPage";
 import GetStartedPage from "@/app/get-started/page";
 import AiPage from "@/app/ai/page";
 import AboutPage from "@/app/about/page";
@@ -25,7 +25,8 @@ import TermsPage from "@/app/terms/page";
  */
 
 const PAGES: Record<string, ComponentType> = {
-  landing: LandingPage,
+  // app/page.tsx only awaits the build-time stats and renders this body; the sync renderer cannot await.
+  landing: () => createElement(LandingPage, { statsSnapshot: null }),
   "get-started": GetStartedPage,
   ai: AiPage,
   about: AboutPage,

src/Web/autopilot-monitor-web/components/__tests__/marketingTracking.guard.test.ts

@@ -11,7 +11,7 @@ vi.mock("@/contexts/AuthContext", () => ({
 // AuthGate only redirects signed-in visitors (it needs the app router) and renders no links.
 vi.mock("@/components/landing/AuthGate", () => ({ AuthGate: () => null }));
 
-import LandingPage from "@/app/page";
+import { LandingPage } from "@/components/landing/LandingPage";
 import GetStartedPage from "@/app/get-started/page";
 import AiPage from "@/app/ai/page";
 import robots from "@/app/robots";
@@ -27,6 +27,8 @@ import { sitePageUrl } from "@/utils/config";
  */
 
 const render = (Page: ComponentType) => renderToStaticMarkup(createElement(Page));
+// app/page.tsx only awaits the build-time stats and renders this body; the sync renderer cannot await.
+const Landing = () => createElement(LandingPage, { statsSnapshot: null });
 const trackIds = (html: string) => [...html.matchAll(/data-track="([^"]+)"/g)].map(m => m[1]);
 const sectionIds = (html: string) => [...html.matchAll(/data-track-section="([^"]+)"/g)].map(m => m[1]);
 const untracked = (html: string) =>
@@ -37,7 +39,7 @@ const untracked = (html: string) =>
 const PAGES: { name: string; Page: ComponentType; sections: string[] }[] = [
   {
     name: "landing",
-    Page: LandingPage,
+    Page: Landing,
     sections: ["hero", "stats", "just_ask", "story", "capabilities", "comparison", "how_it_works", "testimonials", "final_cta"],
   },
   { name: "get-started", Page: GetStartedPage, sections: ["steps", "signup"] },
@@ -60,7 +62,7 @@ describe("marketing page tracking", () => {
   }
 
   it("the landing links to the AI page from the navbar, Then just ask and the footer", () => {
-    const ids = trackIds(render(LandingPage));
+    const ids = trackIds(render(Landing));
     expect(ids).toEqual(expect.arrayContaining(["nav_ai", "just_ask_ai", "footer_ai"]));
   });
 

src/Web/autopilot-monitor-web/components/landing/LandingPage.tsx

@@ -0,0 +1,46 @@
+import { AuthGate } from "./AuthGate";
+import { LandingNavbar } from "./LandingNavbar";
+import { Hero } from "./Hero";
+import { StatsBand } from "./StatsBand";
+import { JustAsk } from "./JustAsk";
+import { Story } from "./Story";
+import { CapabilitiesStrip } from "./CapabilitiesStrip";
+import { Comparison } from "./Comparison";
+import { HowItWorks } from "./HowItWorks";
+import { Testimonials } from "./Testimonials";
+import { FinalCta } from "./FinalCta";
+import { SiteFooter } from "../SiteFooter";
+import { MarketingTracker } from "../MarketingTracker";
+import type { PlatformStatsSnapshot } from "@/lib/platformStats";
+
+/**
+ * Landing page v2 — a scroll story of one enrollment.
+ * All theming goes through the lp-* tokens (globals.css); sections live
+ * in components/landing/. Auth behavior (AuthGate redirect, LoginButton
+ * portal handoff) is unchanged from v1.
+ *
+ * Synchronous on purpose: app/page.tsx awaits the build-time stats and hands
+ * them in, and the marketing guard tests render this body with the sync
+ * renderToStaticMarkup.
+ */
+export function LandingPage({ statsSnapshot }: { statsSnapshot: PlatformStatsSnapshot | null }) {
+  return (
+    <div className="landing-v2 min-h-screen bg-[var(--lp-bg)]">
+      {/* Client component: handles auth redirect + loading overlay */}
+      <AuthGate />
+      <MarketingTracker page="landing">
+        <LandingNavbar />
+        <Hero />
+        <StatsBand snapshot={statsSnapshot} />
+        <JustAsk />
+        <Story />
+        <CapabilitiesStrip />
+        <Comparison />
+        <HowItWorks />
+        <Testimonials />
+        <FinalCta />
+        <SiteFooter />
+      </MarketingTracker>
+    </div>
+  );
+}

src/Web/autopilot-monitor-web/components/landing/StatsBand.tsx

@@ -1,61 +1,12 @@
 "use client";
 
 import { useEffect, useState } from "react";
-
-interface PlatformStatsManifest {
-  latest: string;
-  generatedAtUtc: string;
-}
-
-interface PlatformStatsPayload {
-  totalEnrollments?: number;
-  totalUsers?: number;
-  totalTenants?: number;
-  totalSignedUpTenants?: number;
-  uniqueDeviceModels?: number;
-  totalEventsProcessed?: number;
-  successfulEnrollments?: number;
-  issuesDetected?: number;
-  lastFullCompute?: string;
-  lastUpdated?: string;
-}
-
-function resolvePlatformStatsManifestUrl(rawUrl?: string): string {
-  const trimmed = rawUrl?.trim();
-  if (!trimmed) {
-    return "/platform-stats.json";
-  }
-
-  const hashIndex = trimmed.indexOf("#");
-  const withoutHash = hashIndex >= 0 ? trimmed.slice(0, hashIndex) : trimmed;
-  const hash = hashIndex >= 0 ? trimmed.slice(hashIndex) : "";
-
-  const queryIndex = withoutHash.indexOf("?");
-  const basePath = queryIndex >= 0 ? withoutHash.slice(0, queryIndex) : withoutHash;
-  const query = queryIndex >= 0 ? withoutHash.slice(queryIndex) : "";
-
-  if (/\.json$/i.test(basePath)) {
-    return trimmed;
-  }
-
-  const normalizedBasePath = basePath.endsWith("/") ? basePath.slice(0, -1) : basePath;
-  const manifestPath = `${normalizedBasePath}/platform-stats.json`;
-  return `${manifestPath}${query}${hash}`;
-}
-
-const PLATFORM_STATS_MANIFEST_URL =
-  resolvePlatformStatsManifestUrl(process.env.NEXT_PUBLIC_PLATFORM_STATS_MANIFEST_URL);
-
-interface StatItem {
-  label: string;
-  value: string;
-}
-
-/** 8,341,206 → "8.3M"; smaller values keep their grouped form. */
-function compact(n: number): string {
-  if (n >= 1_000_000) return `${(n / 1_000_000).toFixed(1)}M`;
-  return n.toLocaleString("en-US");
-}
+import {
+  fetchLivePlatformStats,
+  toStatItems,
+  type PlatformStatsSnapshot,
+  type StatItem,
+} from "@/lib/platformStats";
 
 /**
  * Sample values for local development only, where no stats blob is
@@ -71,81 +22,51 @@ const DEV_SAMPLE_STATS: StatItem[] = [
 ];
 
 /**
- * Full-bleed platform stats band under the hero shot. Skeleton while
- * loading; on fetch failure it shows dev sample data locally and
- * disappears entirely in production (never an endless skeleton, never
- * fake numbers).
+ * Full-bleed platform stats band under the hero shot. Starts with the
+ * numbers the build baked in (`snapshot`, lib/platformStats.ts), so the
+ * static HTML carries them for crawlers and LLM fetchers, then swaps in the
+ * live numbers. A failed live read keeps the baked numbers; without either,
+ * it shows dev sample data locally and disappears entirely in production
+ * (never an endless skeleton, never fake numbers). The skeleton only shows
+ * while a page built without a snapshot loads.
  */
-export function StatsBand() {
-  const [stats, setStats] = useState<StatItem[] | null>(null);
+export function StatsBand({ snapshot }: { snapshot: PlatformStatsSnapshot | null }) {
+  const [live, setLive] = useState<StatItem[] | null>(null);
   const [failed, setFailed] = useState(false);
 
   useEffect(() => {
     let cancelled = false;
 
-    const fail = () => {
+    const loadLiveStats = async () => {
+      const payload = await fetchLivePlatformStats();
       if (cancelled) return;
-      if (process.env.NODE_ENV === "development") {
-        setStats(DEV_SAMPLE_STATS);
+      const items = payload ? toStatItems(payload) : [];
+      if (items.length > 0) {
+        setLive(items);
       } else {
         setFailed(true);
       }
     };
 
-    const loadPlatformStats = async () => {
-      try {
-        const manifestResponse = await fetch(PLATFORM_STATS_MANIFEST_URL, { cache: "no-store" });
-        if (!manifestResponse.ok) return fail();
-
-        const manifest = (await manifestResponse.json()) as PlatformStatsManifest;
-        if (!manifest?.latest) return fail();
-
-        const versionedUrl = new URL(manifest.latest, manifestResponse.url).toString();
-        const statsResponse = await fetch(versionedUrl, { cache: "force-cache" });
-        if (!statsResponse.ok) return fail();
-
-        const payload = (await statsResponse.json()) as PlatformStatsPayload;
-        if (cancelled) return;
-
-        const items: StatItem[] = [];
-        if (payload.totalEnrollments) {
-          items.push({ label: "enrollments monitored", value: payload.totalEnrollments.toLocaleString("en-US") });
-        }
-        if (payload.issuesDetected) {
-          items.push({ label: "issues detected", value: payload.issuesDetected.toLocaleString("en-US") });
-        }
-        if (payload.totalSignedUpTenants) {
-          items.push({ label: "organisations", value: payload.totalSignedUpTenants.toLocaleString("en-US") });
-        }
-        if (payload.uniqueDeviceModels) {
-          items.push({ label: "device models", value: payload.uniqueDeviceModels.toLocaleString("en-US") });
-        }
-        if (payload.totalEventsProcessed) {
-          items.push({ label: "events processed", value: compact(payload.totalEventsProcessed) });
-        }
-        if (items.length > 0) {
-          setStats(items);
-        } else {
-          fail();
-        }
-      } catch {
-        // The band is decorative and must never break the page.
-        fail();
-      }
-    };
-
-    loadPlatformStats();
+    loadLiveStats();
     return () => {
       cancelled = true;
     };
   }, []);
 
-  if (failed) {
+  const devFallback = failed && process.env.NODE_ENV === "development" ? DEV_SAMPLE_STATS : null;
+  const stats = live ?? snapshot?.items ?? devFallback;
+  if (!stats && failed) {
     return null;
   }
 
   return (
-    <section data-track-section="stats" className="border-y border-[var(--lp-line-soft)] bg-[var(--lp-surface-2)]">
+    <section
+      data-track-section="stats"
+      // Which build snapshot the static HTML carries; deploy-web.yml warns when it is missing.
+      data-stats-snapshot={snapshot ? (snapshot.asOf ?? "") : undefined}
+      className="border-y border-[var(--lp-line-soft)] bg-[var(--lp-surface-2)]"
+    >
       <div className="max-w-7xl mx-auto px-6 grid grid-cols-2 sm:grid-cols-3 lg:grid-cols-5 gap-y-6 py-8 lg:divide-x lg:divide-[var(--lp-line)]">
         {(stats ?? Array.from({ length: 5 }, () => null)).map((item, i) =>
           item ? (

src/Web/autopilot-monitor-web/lib/__tests__/apiClient.guard.baseline.ts

@@ -6,7 +6,6 @@
 /** Files that keep a raw site for a stated reason; they never leave the baseline. */
 export const PERMANENT: Record<string, string> = {
   "contexts/AuthContext.tsx": "auth/me bootstrap runs before the auth context exists: raw fetch by design",
-  "components/landing/StatsBand.tsx": "unauthenticated public blob manifest, not the API",
   "app/health-check/page.tsx": "/version.json of the SWA itself, not the API",
   "app/dashboard/hooks/deleteSessionResponse.ts": "safeJson on the 202 Response of the delete-cascade classifier (refusals arrive as ApiError)",
   "app/settings/TenantConfigContext.tsx": "consent return path routes on TokenExpiredError (router.replace); the access check rethrows it as a non-outcome",
@@ -33,7 +32,6 @@ export const DEDUPEDAUTHFETCH_BASELINE: Record<string, number> = {
 export const JSONPARSE_BASELINE: Record<string, number> = {
   "app/dashboard/hooks/deleteSessionResponse.ts": 1,
   "app/health-check/page.tsx": 1,
-  "components/landing/StatsBand.tsx": 2,
   "contexts/AuthContext.tsx": 2,
 };
 

src/Web/autopilot-monitor-web/lib/__tests__/platformStats.test.ts

@@ -0,0 +1,188 @@
+import { afterEach, beforeEach, describe, expect, it, vi, type MockInstance } from "vitest";
+import {
+  fetchLivePlatformStats,
+  loadPlatformStatsSnapshot,
+  resolvePlatformStatsManifestUrl,
+  toStatItems,
+} from "../platformStats";
+
+const CONTAINER = "https://stats.example.test/publicstats";
+const MANIFEST_URL = `${CONTAINER}/platform-stats.json`;
+const PAYLOAD_URL = `${CONTAINER}/platform-stats.2026-10-02T140005Z.json`;
+
+/** What the backend publishes (MaintenanceService.TryPublishPlatformStatsJsonAsync). */
+const MANIFEST = { latest: "platform-stats.2026-10-02T140005Z.json", generatedAtUtc: "2026-10-02T14:00:05.1234567Z" };
+const PAYLOAD = {
+  totalEnrollments: 12481,
+  totalUsers: 310,
+  totalTenants: 92,
+  totalSignedUpTenants: 87,
+  uniqueDeviceModels: 214,
+  totalEventsProcessed: 8341206,
+  successfulEnrollments: 11020,
+  issuesDetected: 1847,
+  lastFullCompute: "2026-10-02T14:00:03.1234567Z",
+  lastUpdated: "2026-10-02T14:00:03.1234567Z",
+};
+
+const BAND = [
+  { label: "enrollments monitored", value: "12,481" },
+  { label: "issues detected", value: "1,847" },
+  { label: "organisations", value: "87" },
+  { label: "device models", value: "214" },
+  { label: "events processed", value: "8.3M" },
+];
+
+function json(body: unknown, status = 200): Response {
+  return new Response(JSON.stringify(body), { status, headers: { "Content-Type": "application/json" } });
+}
+
+/** Answers by URL; anything not listed is a 404. */
+function serve(routes: Record<string, () => Response>) {
+  const fetchMock = vi.fn<(input: string, init?: RequestInit) => Promise<Response>>(async input =>
+    routes[input]?.() ?? new Response("not found", { status: 404 }));
+  vi.stubGlobal("fetch", fetchMock);
+  return fetchMock;
+}
+
+const BOTH_FILES = { [MANIFEST_URL]: () => json(MANIFEST), [PAYLOAD_URL]: () => json(PAYLOAD) };
+
+afterEach(() => {
+  vi.unstubAllGlobals();
+  vi.restoreAllMocks();
+});
+
+describe("resolvePlatformStatsManifestUrl", () => {
+  it("falls back to the same-origin manifest without a configured URL", () => {
+    expect([undefined, "", "  "].map(resolvePlatformStatsManifestUrl)).toEqual(Array(3).fill("/platform-stats.json"));
+  });
+
+  it("appends the manifest name to a container URL, with or without a trailing slash", () => {
+    expect(resolvePlatformStatsManifestUrl(CONTAINER)).toBe(MANIFEST_URL);
+    expect(resolvePlatformStatsManifestUrl(`${CONTAINER}/`)).toBe(MANIFEST_URL);
+  });
+
+  it("keeps a URL that already names a JSON file", () => {
+    expect(resolvePlatformStatsManifestUrl(MANIFEST_URL)).toBe(MANIFEST_URL);
+    expect(resolvePlatformStatsManifestUrl(`${CONTAINER}/custom.JSON`)).toBe(`${CONTAINER}/custom.JSON`);
+  });
+
+  it("keeps query and hash behind the appended manifest name", () => {
+    expect(resolvePlatformStatsManifestUrl(`${CONTAINER}?v=1#x`)).toBe(`${MANIFEST_URL}?v=1#x`);
+  });
+});
+
+describe("toStatItems", () => {
+  it("maps the band's figures in display order", () => {
+    expect(toStatItems(PAYLOAD)).toEqual(BAND);
+  });
+
+  it("leaves out figures that are missing, zero, negative or not a finite number", () => {
+    const payload = {
+      totalEnrollments: 0,
+      issuesDetected: -5,
+      totalSignedUpTenants: Number.POSITIVE_INFINITY,
+      uniqueDeviceModels: "214" as unknown as number,
+      totalEventsProcessed: 999_999,
+    };
+    expect(toStatItems(payload)).toEqual([{ label: "events processed", value: "999,999" }]);
+    expect(toStatItems({})).toEqual([]);
+  });
+});
+
+describe("fetchLivePlatformStats", () => {
+  it("revalidates the manifest and takes the immutable file it names from the browser cache", async () => {
+    const fetchMock = serve(BOTH_FILES);
+
+    expect(await fetchLivePlatformStats(MANIFEST_URL)).toEqual(PAYLOAD);
+    expect(fetchMock.mock.calls).toEqual([
+      [MANIFEST_URL, { cache: "no-cache" }],
+      [PAYLOAD_URL, { cache: "default" }],
+    ]);
+  });
+
+  it("resolves the versioned file against the manifest as served, after redirects", async () => {
+    const redirected = json(MANIFEST);
+    Object.defineProperty(redirected, "url", { value: "https://stats.example.test/v2/platform-stats.json" });
+    const fetchMock = serve({
+      [MANIFEST_URL]: () => redirected,
+      "https://stats.example.test/v2/platform-stats.2026-10-02T140005Z.json": () => json(PAYLOAD),
+    });
+
+    expect(await fetchLivePlatformStats(MANIFEST_URL)).toEqual(PAYLOAD);
+    expect(fetchMock).toHaveBeenCalledTimes(2);
+  });
+
+  const failures: [string, Record<string, () => Response>][] = [
+    ["the manifest is missing", { [PAYLOAD_URL]: () => json(PAYLOAD) }],
+    ["the manifest names no file", { [MANIFEST_URL]: () => json({ generatedAtUtc: MANIFEST.generatedAtUtc }) }],
+    ["the manifest is not JSON", { [MANIFEST_URL]: () => new Response("<html></html>") }],
+    ["the manifest names a file on another origin", { [MANIFEST_URL]: () => json({ latest: "https://elsewhere.example.test/stats.json" }) }],
+    ["the versioned file is missing", { [MANIFEST_URL]: () => json(MANIFEST) }],
+    ["the versioned file holds no object", { [MANIFEST_URL]: () => json(MANIFEST), [PAYLOAD_URL]: () => json(42) }],
+  ];
+  for (const [name, routes] of failures) {
+    it(`returns null when ${name}`, async () => {
+      serve(routes);
+      expect(await fetchLivePlatformStats(MANIFEST_URL)).toBeNull();
+    });
+  }
+
+  it("returns null when the network fails", async () => {
+    vi.stubGlobal("fetch", vi.fn().mockRejectedValue(new TypeError("Failed to fetch")));
+    expect(await fetchLivePlatformStats(MANIFEST_URL)).toBeNull();
+  });
+});
+
+describe("loadPlatformStatsSnapshot", () => {
+  let log: MockInstance<typeof console.log>;
+  let warn: MockInstance<typeof console.warn>;
+  beforeEach(() => {
+    log = vi.spyOn(console, "log").mockImplementation(() => undefined);
+    warn = vi.spyOn(console, "warn").mockImplementation(() => undefined);
+  });
+
+  it("bakes nothing and sends no request without an absolute URL (local and CI builds)", async () => {
+    const fetchMock = serve(BOTH_FILES);
+
+    expect(await loadPlatformStatsSnapshot("/platform-stats.json")).toBeNull();
+    expect(fetchMock).not.toHaveBeenCalled();
+    expect(warn).not.toHaveBeenCalled();
+  });
+
+  it("returns the band's items and the stats timestamp, read past Next's fetch cache within a deadline", async () => {
+    const fetchMock = serve(BOTH_FILES);
+
+    expect(await loadPlatformStatsSnapshot(MANIFEST_URL)).toEqual({ items: BAND, asOf: PAYLOAD.lastUpdated });
+    const inits = fetchMock.mock.calls.map(([, init]) => init);
+    expect(inits).toHaveLength(2);
+    for (const init of inits) {
+      expect(init?.cache).toBe("no-store");
+      expect(init?.signal).toBeInstanceOf(AbortSignal);
+    }
+    expect(inits[0]?.signal).toBe(inits[1]?.signal);
+    expect(log).toHaveBeenCalledWith(expect.stringContaining(`from ${MANIFEST.latest} (as of ${PAYLOAD.lastUpdated})`));
+  });
+
+  it("fails soft with the reason in the build log when the blob does not answer", async () => {
+    serve({ [MANIFEST_URL]: () => new Response("unavailable", { status: 503 }) });
+
+    expect(await loadPlatformStatsSnapshot(MANIFEST_URL)).toBeNull();
+    expect(warn).toHaveBeenCalledWith(expect.stringContaining("HTTP 503"));
+  });
+
+  it("names the network cause behind Node's generic fetch failure", async () => {
+    const failure = new TypeError("fetch failed", { cause: new Error("getaddrinfo ENOTFOUND stats.example.test") });
+    vi.stubGlobal("fetch", vi.fn().mockRejectedValue(failure));
+
+    expect(await loadPlatformStatsSnapshot(MANIFEST_URL)).toBeNull();
+    expect(warn).toHaveBeenCalledWith(expect.stringContaining("fetch failed (getaddrinfo ENOTFOUND stats.example.test)"));
+  });
+
+  it("bakes nothing when the file holds no positive figure", async () => {
+    serve({ [MANIFEST_URL]: () => json(MANIFEST), [PAYLOAD_URL]: () => json({ ...PAYLOAD, totalEnrollments: 0, issuesDetected: 0, totalSignedUpTenants: 0, uniqueDeviceModels: 0, totalEventsProcessed: 0 }) });
+
+    expect(await loadPlatformStatsSnapshot(MANIFEST_URL)).toBeNull();
+    expect(warn).toHaveBeenCalledWith(expect.stringContaining("no positive figure"));
+  });
+});

src/Web/autopilot-monitor-web/lib/__tests__/scriptExecutions.test.ts

@@ -1201,3 +1201,81 @@ describe("isOnOffsetGrid", () => {
     expect(isOnOffsetGrid(0)).toBe(false);
   });
 });
+
+describe("reduceScriptEvents — correction from IME's saved result (D-316)", () => {
+  const POLICY = "d94468af-6ebe-4e94-9901-2a62d33ea6c1";
+  const OWN = "=== Autopilot Monitor Bootstrap Started =====\nBootstrap script version: v2.5\nInstaller finished (exit code 0).";
+  const FOREIGN = "VERBOSE: === Sample Suite Detection Started ===\nWARNING: === DETECTION FAILED ===";
+  const correction = (data: Record<string, unknown>, at = 60): ScriptInputEvent => ({
+    timestamp: ts(at),
+    eventType: "script_output_reconciliation",
+    data: { policyId: POLICY, scriptType: "platform", ...data },
+  });
+
+  it("a foreign end block is replaced: the script's own output, no exit code, Success", () => {
+    const items = reduceScriptEvents([
+      finalEvent({ eventType: "script_failed", data: { policyId: POLICY, scriptType: "platform", runId: "r1", result: "Success", exitCode: "1", stdout: FOREIGN } }),
+      correction({ runId: "r1", outcome: "foreign", result: "Success", stdout: OWN, stderr: "", previousExitCode: "1" }),
+    ]);
+    expect(items).toHaveLength(1);
+    expect(items[0].state).toBe("Success");
+    expect(items[0].exitCode).toBeUndefined();
+    expect(items[0].stdout).toBe(OWN);
+    expect(items[0].stdout).not.toContain("Detection");
+    expect(items[0].outputCorrection).toBe("foreign");
+    expect(items[0].bootstrapVersion).toBe("2.5");
+  });
+
+  it("an incomplete output is completed and the exit code stands", () => {
+    const items = reduceScriptEvents([
+      finalEvent({ data: { policyId: POLICY, scriptType: "platform", runId: "r2", result: "Success", exitCode: "0" } }),
+      correction({ runId: "r2", outcome: "repaired", result: "Success", stdout: OWN, stderr: "" }),
+    ]);
+    expect(items[0].exitCode).toBe(0);
+    expect(items[0].stdout).toBe(OWN);
+    expect(items[0].outputCorrection).toBe("repaired");
+  });
+
+  it("a stdout split into stderr is mended: the empty stderr clears the failure", () => {
+    const items = reduceScriptEvents([
+      finalEvent({ eventType: "script_failed", data: { policyId: POLICY, scriptType: "platform", runId: "r3", result: "Success", exitCode: "0", stdout: "Copying files", stderr: "0 errors\nDone, error =" } }),
+      correction({ runId: "r3", outcome: "repaired", result: "Success", stdout: "Copying files, error = 0 errors\nDone", stderr: "" }),
+    ]);
+    expect(items[0].state).toBe("Success");
+    expect(items[0].stderr).toBeUndefined();
+    expect(items[0].stdout).toBe("Copying files, error = 0 errors\nDone");
+  });
+
+  it("a correction only applies to the run it names", () => {
+    const items = reduceScriptEvents([
+      finalEvent({ eventType: "script_failed", data: { policyId: POLICY, scriptType: "platform", runId: "r4", result: "Success", exitCode: "1", stdout: FOREIGN } }),
+      correction({ runId: "another-run", outcome: "foreign", result: "Success", stdout: OWN, stderr: "" }),
+    ]);
+    expect(items[0].state).toBe("Failed");
+    expect(items[0].exitCode).toBe(1);
+    expect(items[0].outputCorrection).toBeUndefined();
+  });
+
+  it("a correction without a stdout key keeps the emitted stdout", () => {
+    const items = reduceScriptEvents([
+      finalEvent({ eventType: "script_failed", data: { policyId: POLICY, scriptType: "platform", runId: "r5", result: "Failed", exitCode: "1", stdout: "partial" } }),
+      correction({ runId: "r5", outcome: "repaired", result: "Failed", stderr: "Access denied" }),
+    ]);
+    expect(items[0].stdout).toBe("partial");
+    expect(items[0].stderr).toBe("Access denied");
+    expect(items[0].state).toBe("Failed");
+  });
+
+  it("two runs of the same script never surface the corrected run's foreign output", () => {
+    const items = reduceScriptEvents([
+      finalEvent({ ts: 0, data: { policyId: POLICY, scriptType: "platform", runId: "old", result: "Success", exitCode: "0", runContext: "System", stdout: OWN } }),
+      finalEvent({ ts: 30, eventType: "script_failed", data: { policyId: POLICY, scriptType: "platform", runId: "r6", result: "Success", exitCode: "1", runContext: "System", stdout: FOREIGN } }),
+      correction({ runId: "r6", outcome: "foreign", result: "Success", stdout: OWN, stderr: "" }),
+    ]);
+    expect(items).toHaveLength(1);
+    expect(items[0].stdout).toBe(OWN);
+    expect(items[0].stdout).not.toContain("Detection");
+    expect(items[0].state).toBe("Success");
+    expect(items[0].exitCode === 1).toBe(false);
+  });
+});

src/Web/autopilot-monitor-web/lib/__tests__/standby.test.ts

@@ -95,6 +95,17 @@ describe("enrollmentWindowOf", () => {
     expect(w).toEqual({ startMs: Date.parse("2026-09-09T06:32:46Z"), endMs: Date.parse("2026-09-09T06:40:00Z") });
   });
 
+  it("ignores update and servicing rows backfilled from before the agent started", () => {
+    // D-315: the update watchers deliver rows with their event-log time up to 60 min before the agent.
+    const w = enrollmentWindowOf([
+      activity(1, "2026-10-03T08:51:58Z", "windows_update_started", "WindowsUpdateWatcher"),
+      activity(2, "2026-10-03T08:52:37Z", "windows_update_servicing", "ServicingWatcher"),
+      activity(3, "2026-10-03T08:56:46Z", "ime_agent_version", "ImeLogTracker"),
+      activity(4, "2026-10-03T10:08:09Z", "enrollment_complete", "DecisionEngine"),
+    ]);
+    expect(w).toEqual({ startMs: Date.parse("2026-10-03T08:56:46Z"), endMs: Date.parse("2026-10-03T10:08:09Z") });
+  });
+
   it("is null without activity events", () => {
     expect(enrollmentWindowOf([activity(1, "2026-09-09T06:00:00Z", "system_clock_changed", "SystemTimelineWatcher")])).toBeNull();
     expect(enrollmentWindowOf([])).toBeNull();

src/Web/autopilot-monitor-web/lib/platformStats.ts

@@ -0,0 +1,180 @@
+import type { PlatformStats } from "@/utils/wire-types.generated";
+
+/**
+ * The landing page's platform stats. A public blob container holds a manifest
+ * (`platform-stats.json`, rewritten by the backend maintenance run every 2 hours) that names the
+ * versioned file with the numbers (`latest`, relative to the manifest).
+ *
+ * Read twice: once by `next build`, which bakes the numbers of that moment into the static HTML
+ * (crawlers and LLM fetchers run no JS and would otherwise see only a skeleton), and again by
+ * every browser, which swaps in the live numbers (components/landing/StatsBand.tsx). Both reads
+ * share the URL, fetch and formatting rules here.
+ */
+
+interface PlatformStatsManifest {
+  latest: string;
+  generatedAtUtc: string;
+}
+
+/**
+ * The versioned file. The backend writes it field by field under the names of the wire type
+ * PlatformStats; every field stays optional because the body is parsed, not trusted.
+ */
+export type PlatformStatsPayload = Partial<PlatformStats>;
+
+export interface StatItem {
+  label: string;
+  value: string;
+}
+
+/** The numbers baked into the static HTML at build time. */
+export interface PlatformStatsSnapshot {
+  items: StatItem[];
+  /** When the backend computed them (the payload's lastUpdated): page marker and build log. */
+  asOf: string | null;
+}
+
+export function resolvePlatformStatsManifestUrl(rawUrl?: string): string {
+  const trimmed = rawUrl?.trim();
+  if (!trimmed) {
+    return "/platform-stats.json";
+  }
+
+  const hashIndex = trimmed.indexOf("#");
+  const withoutHash = hashIndex >= 0 ? trimmed.slice(0, hashIndex) : trimmed;
+  const hash = hashIndex >= 0 ? trimmed.slice(hashIndex) : "";
+
+  const queryIndex = withoutHash.indexOf("?");
+  const basePath = queryIndex >= 0 ? withoutHash.slice(0, queryIndex) : withoutHash;
+  const query = queryIndex >= 0 ? withoutHash.slice(queryIndex) : "";
+
+  if (/\.json$/i.test(basePath)) {
+    return trimmed;
+  }
+
+  const normalizedBasePath = basePath.endsWith("/") ? basePath.slice(0, -1) : basePath;
+  const manifestPath = `${normalizedBasePath}/platform-stats.json`;
+  return `${manifestPath}${query}${hash}`;
+}
+
+export const PLATFORM_STATS_MANIFEST_URL =
+  resolvePlatformStatsManifestUrl(process.env.NEXT_PUBLIC_PLATFORM_STATS_MANIFEST_URL);
+
+/** Budget for both build-time requests together: a slow blob must not stall the deploy. */
+const BUILD_FETCH_TIMEOUT_MS = 10_000;
+
+/** 8,341,206 → "8.3M"; smaller values keep their grouped form. */
+function compact(n: number): string {
+  if (n >= 1_000_000) return `${(n / 1_000_000).toFixed(1)}M`;
+  return n.toLocaleString("en-US");
+}
+
+function grouped(n: number): string {
+  return n.toLocaleString("en-US");
+}
+
+/** The band's figures in display order. */
+const STAT_FIELDS: { field: keyof PlatformStats; label: string; format: (n: number) => string }[] = [
+  { field: "totalEnrollments", label: "enrollments monitored", format: grouped },
+  { field: "issuesDetected", label: "issues detected", format: grouped },
+  { field: "totalSignedUpTenants", label: "organisations", format: grouped },
+  { field: "uniqueDeviceModels", label: "device models", format: grouped },
+  { field: "totalEventsProcessed", label: "events processed", format: compact },
+];
+
+/**
+ * The band's items. Only finite positive numbers count: the values end up in the static HTML,
+ * and a zero means "not computed yet", not a figure to publish.
+ */
+export function toStatItems(payload: PlatformStatsPayload): StatItem[] {
+  return STAT_FIELDS.flatMap(({ field, label, format }) => {
+    const value = payload[field];
+    return typeof value === "number" && Number.isFinite(value) && value > 0
+      ? [{ label, value: format(value) }]
+      : [];
+  });
+}
+
+/** One read: the numbers and the versioned file they came from (named in the build log). */
+interface PlatformStatsRead {
+  payload: PlatformStatsPayload;
+  file: string;
+}
+
+/**
+ * Manifest, then the file it names. Throws with the reason; the callers decide what to report.
+ * Each hop takes its own request options: the manifest changes with every publish, a versioned
+ * file never does.
+ */
+async function readPlatformStats(
+  manifestUrl: string,
+  manifestInit: RequestInit,
+  payloadInit: RequestInit = manifestInit,
+): Promise<PlatformStatsRead> {
+  const manifestResponse = await fetch(manifestUrl, manifestInit);
+  if (!manifestResponse.ok) throw new Error(`${manifestUrl} answered HTTP ${manifestResponse.status}`);
+  const manifest = (await manifestResponse.json()) as Partial<PlatformStatsManifest> | null;
+  if (typeof manifest?.latest !== "string" || !manifest.latest) {
+    throw new Error(`${manifestUrl} names no versioned file`);
+  }
+
+  // Relative to the manifest as served (after redirects); a hand-built Response has no url.
+  const base = manifestResponse.url || manifestUrl;
+  const payloadUrl = new URL(manifest.latest, base);
+  if (payloadUrl.origin !== new URL(base).origin) {
+    throw new Error(`${manifestUrl} names a file on another origin`);
+  }
+
+  const payloadResponse = await fetch(payloadUrl.toString(), payloadInit);
+  if (!payloadResponse.ok) throw new Error(`${payloadUrl} answered HTTP ${payloadResponse.status}`);
+  const payload: unknown = await payloadResponse.json();
+  if (typeof payload !== "object" || payload === null) throw new Error(`${payloadUrl} holds no stats object`);
+  return { payload: payload as PlatformStatsPayload, file: manifest.latest };
+}
+
+/**
+ * The browser's read. The manifest is revalidated on every load; the versioned file it names
+ * comes from the browser cache once fetched: the backend writes a new name per publish and serves
+ * it immutable (MaintenanceService.PlatformStatsVersionedFileName).
+ */
+export async function fetchLivePlatformStats(
+  manifestUrl: string = PLATFORM_STATS_MANIFEST_URL,
+): Promise<PlatformStatsPayload | null> {
+  try {
+    return (await readPlatformStats(manifestUrl, { cache: "no-cache" }, { cache: "default" })).payload;
+  } catch {
+    // The band is decorative: a failed read only means no live numbers.
+    return null;
+  }
+}
+
+/**
+ * The build's read (app/page.tsx), once per `next build`. Only for an absolute URL: local and CI
+ * builds have none (the relative fallback exists only in a browser) and bake nothing.
+ * `no-store` keeps the read out of Next's fetch cache, which would otherwise hand the next build
+ * on the same machine the previous numbers; the page is `force-static`, so `no-store` stays
+ * legal in the static export. Fail-soft: without a snapshot the page ships the skeleton and
+ * browsers load the numbers live, as before; deploy-web.yml reports it as a warning.
+ */
+export async function loadPlatformStatsSnapshot(
+  manifestUrl: string = PLATFORM_STATS_MANIFEST_URL,
+): Promise<PlatformStatsSnapshot | null> {
+  if (!/^https?:\/\//i.test(manifestUrl)) return null;
+  try {
+    const { payload, file } = await readPlatformStats(manifestUrl, {
+      cache: "no-store",
+      signal: AbortSignal.timeout(BUILD_FETCH_TIMEOUT_MS),
+    });
+    const items = toStatItems(payload);
+    if (items.length === 0) throw new Error(`${file} holds no positive figure`);
+    const asOf = typeof payload.lastUpdated === "string" ? payload.lastUpdated : null;
+    console.log(`Platform stats baked into the landing page from ${file} (as of ${asOf ?? "unknown"}).`);
+    return { items, asOf };
+  } catch (err) {
+    // Node's fetch reports every network failure as "fetch failed" and keeps the reason in `cause`.
+    const cause = err instanceof Error && err.cause instanceof Error ? ` (${err.cause.message})` : "";
+    const reason = err instanceof Error ? `${err.message}${cause}` : String(err);
+    console.warn(`Platform stats not baked into the landing page; browsers still load them live. ${reason}`);
+    return null;
+  }
+}

src/Web/autopilot-monitor-web/lib/scriptExecutions.ts

@@ -36,8 +36,19 @@ interface ScriptEventData {
   sourceOffsetOrigin?: string;
   /** "true" when the line's own timestamp was rejected and the event was stamped from the clock. */
   derivedTimestamp?: string | boolean;
+  /** Identity of one platform-script run; a script_output_reconciliation names the run it corrects (agents from 2026-10 on). */
+  runId?: string;
+  /** On script_output_reconciliation: "foreign" (the run had another script's end block) or "repaired". */
+  outcome?: string;
 }
 
+/**
+ * A platform run corrected after the fact from IME's saved result (D-316). Its `runId` names the
+ * script_completed/script_failed it corrects; a present `stdout`/`stderr` key replaces the emitted
+ * value (empty clears it), `outcome` "foreign" makes the emitted exit code unverified.
+ */
+export const SCRIPT_OUTPUT_RECONCILIATION = "script_output_reconciliation";
+
 export interface ScriptItem {
   policyId: string;
   scriptType: string;        // "platform" | "remediation"
@@ -80,6 +91,12 @@ export interface ScriptItem {
   state: "Running" | "Success" | "Failed";
   timestamp: string;
   bootstrapVersion?: string | null;
+  /**
+   * Set when IME's saved result corrected the run (script_output_reconciliation): "foreign" — the
+   * log had given the run another script's end block, so the output shown is the script's own from
+   * IME and the exit code is unknown; "repaired" — the log had delivered the output incomplete.
+   */
+  outputCorrection?: "foreign" | "repaired";
   /**
    * Set by applyObservationEnd, never by the fold: the script was still running when the
    * session's observation ended. Terminal, neither a failure nor a success — the outcome was
@@ -198,6 +215,9 @@ export function partitionHistoricScriptEvents(events: ScriptInputEvent[]): Histo
 function dataCompleteness(item: ScriptItem): number {
   let score = 0;
   if (item.exitCode != null) score += 4; // exit code is the most important signal
+  // A run corrected from IME's saved result lost a foreign exit code, not data: it must not lose
+  // the merge against a sibling run for that.
+  if (item.outputCorrection === "foreign") score += 4;
   if (item.result) score += 2;
   if (item.complianceResult) score += 2;
   if (item.remediationStatus != null) score += 1;
@@ -224,6 +244,18 @@ export function toNumber(v: unknown): number | undefined {
   return undefined;
 }
 
+/**
+ * The value a correction publishes for `key`, or the emitted one: a present key replaces it (an
+ * empty string clears it), an absent key keeps it.
+ */
+function correctedText(correction: ScriptEventData | undefined, key: "stdout" | "stderr", emitted: unknown): string | undefined {
+  if (correction && typeof correction[key] === "string") {
+    const value = correction[key] as string;
+    return value.length > 0 ? value : undefined;
+  }
+  return typeof emitted === "string" ? emitted : undefined;
+}
+
 /** Map RemediationStatus enum to the human-readable label shown in the detail panel. */
 export function mapRemediationStatus(status?: number): string | null {
   switch (status) {
@@ -378,7 +410,14 @@ export function reduceScriptEvents(events: ScriptInputEvent[]): ScriptItem[] {
   // script_started events per (policyId, scriptType) in timestamp order — the start line a
   // final is paired with when its run duration is judged (see judgeDurationPair).
   const startsByPolicy = new Map<string, ScriptInputEvent[]>();
+  // IME's saved result corrects a platform run after the fact; the correction names the run.
+  const correctionsByRunId = new Map<string, ScriptEventData>();
   for (const evt of sorted) {
+    if (evt.eventType === SCRIPT_OUTPUT_RECONCILIATION) {
+      const c = evt.data as ScriptEventData | undefined;
+      if (c && typeof c.runId === "string" && c.runId.length > 0) correctionsByRunId.set(c.runId, c);
+      continue;
+    }
     if (evt.eventType !== "script_started") continue;
     const d = evt.data as ScriptEventData | undefined;
     const startPolicyId = d?.policyId ?? d?.policy_id;
@@ -402,7 +441,10 @@ export function reduceScriptEvents(events: ScriptInputEvent[]): ScriptItem[] {
     const key = `${dedupeId}-${scriptType}-${scriptPart ?? ""}`;
     if (policyId) policyIdsWithFinal.add(`${policyId}-${scriptType}`);
 
-    const exitCode = toNumber(d.exitCode ?? d.exit_code);
+    const correction = typeof d.runId === "string" ? correctionsByRunId.get(d.runId) : undefined;
+    const outputCorrection = correction ? (correction.outcome === "foreign" ? "foreign" : "repaired") : undefined;
+    // A foreign end block's exit code belongs to another script: unknown, not the emitted value.
+    const exitCode = outputCorrection === "foreign" ? undefined : toNumber(d.exitCode ?? d.exit_code);
 
     // Duration normalization — the wire field durationSeconds carries two different
     // semantics, named by durationBasis (see the ScriptItem field docs):
@@ -435,8 +477,9 @@ export function reduceScriptEvents(events: ScriptInputEvent[]): ScriptItem[] {
     const remediationStatus = toNumber(d.remediationStatus ?? d.remediation_status);
     const targetType = toNumber(d.targetType ?? d.target_type);
     const errorCode = toNumber(d.errorCode ?? d.error_code);
-    const stdout = typeof d.stdout === "string" ? d.stdout : undefined;
-    const stderr = typeof d.stderr === "string" ? d.stderr : undefined;
+    const stdout = correctedText(correction, "stdout", d.stdout);
+    const stderr = correctedText(correction, "stderr", d.stderr);
+    const result = (typeof correction?.result === "string" ? correction.result : undefined) ?? d.result;
     const hasStderr = !!stderr && stderr.trim().length > 0;
 
     // State derivation — rules in priority order (mirrors the agent's EmitScriptCompleted):
@@ -450,8 +493,10 @@ export function reduceScriptEvents(events: ScriptInputEvent[]): ScriptItem[] {
     //   3. Defensive: explicit script_failed eventType OR result === "Failed" → Failed.
     const isHealthComplianceReport = scriptType === "remediation"
       && (scriptPart === "detection" || scriptPart === "post-detection");
-    const isFailureSignal = evt.eventType === "script_failed"
-      || d.result === "Failed"
+    // A corrected run is judged on its corrected data: the agent chose script_failed from the
+    // emitted values the correction replaced.
+    const isFailureSignal = (!correction && evt.eventType === "script_failed")
+      || result === "Failed"
       || (!isHealthComplianceReport && (hasStderr || (exitCode != null && exitCode !== 0)));
 
     const candidate: ScriptItem = {
@@ -460,7 +505,7 @@ export function reduceScriptEvents(events: ScriptInputEvent[]): ScriptItem[] {
       scriptPart,
       runContext: d.runContext ?? d.run_context,
       exitCode,
-      result: d.result,
+      result,
       complianceResult: d.complianceResult ?? d.compliance_result,
       remediationStatus,
       targetType,
@@ -476,6 +521,7 @@ export function reduceScriptEvents(events: ScriptInputEvent[]): ScriptItem[] {
       timestamp: evt.timestamp,
       bootstrapVersion: scriptType === "platform" ? extractBootstrapVersion(stdout) : null,
       isIncomplete: false,
+      outputCorrection,
     };
 
     // Keep the most-complete entry, but merge the duration fields across both: the

src/Web/autopilot-monitor-web/lib/standby.ts

@@ -1,4 +1,8 @@
 import type { EnrollmentEvent } from "@/types";
+import { SHARED_MANIFEST } from "@/utils/shared-manifests.generated";
+
+/** Sources whose rows never set a session's start (backend `Constants.EventSources.SessionAnchorIneligible`). */
+const ANCHOR_INELIGIBLE_SOURCES: ReadonlySet<string> = new Set(SHARED_MANIFEST.sessionAnchorIneligibleSources);
 
 export interface StandbyWindow {
   startMs: number;
@@ -7,17 +11,18 @@ export interface StandbyWindow {
 
 /**
  * The enrollment window as the session page measures its duration: first activity event →
- * `enrollment_complete`, or the last activity event while no verdict exists. System-timeline
- * rows (clock steps, sleep episodes) are excluded — they are backfilled from the Windows event
- * log with timestamps up to 24 h before the agent started and would drag the start into
- * pre-enrollment idle time. Null when the session has no activity events.
+ * `enrollment_complete`, or the last activity event while no verdict exists. Backfilled
+ * environment rows (clock steps, sleep, update and servicing activity) are excluded, as in the
+ * backend's session anchor — they carry Windows event-log timestamps from before the agent
+ * started and would drag the start into pre-enrollment time. Null when the session has no
+ * activity events.
  */
 export function enrollmentWindowOf(events: EnrollmentEvent[]): StandbyWindow | null {
   let startMs = Number.POSITIVE_INFINITY;
   let lastMs = Number.NEGATIVE_INFINITY;
   let completeMs: number | null = null;
   for (const e of events) {
-    if (e.source === "SystemTimelineWatcher") continue;
+    if (ANCHOR_INELIGIBLE_SOURCES.has(e.source)) continue;
     const t = new Date(e.timestamp).getTime();
     if (!Number.isFinite(t)) continue;
     if (t < startMs) startMs = t;

src/Web/autopilot-monitor-web/scripts/generate-lastmod.js

@@ -18,7 +18,7 @@ const OUTPUT_FILE = path.join(WEB_ROOT, "utils/page-lastmod.generated.ts");
 // fails the build for any URL missing here. Documentation and the changelog
 // live on docs.autopilotmonitor.com (GitBook) and are not part of this site.
 const PAGE_MAP = {
-  "/": ["app/page.tsx"],
+  "/": ["app/page.tsx", "components/landing/LandingPage.tsx"],
   "/about": ["app/about/page.tsx", "app/about/faq.ts"],
   "/ai": ["app/ai/page.tsx", "components/ai/questions.ts"],
   "/get-started": ["app/get-started/page.tsx"],

src/Web/autopilot-monitor-web/utils/shared-manifests.generated.ts

@@ -503,6 +503,11 @@ export const SHARED_MANIFEST = {
     "ime",
     "realmjoin"
   ],
+  "sessionAnchorIneligibleSources": [
+    "SystemTimelineWatcher",
+    "WindowsUpdateWatcher",
+    "ServicingWatcher"
+  ],
   "ruleSubmissionKinds": [
     "gather",
     "analyze"
@@ -895,6 +900,7 @@ export const SHARED_MANIFEST = {
     "remote_config_fetch_failed",
     "script_completed",
     "script_failed",
+    "script_output_reconciliation",
     "script_recurrence_summary",
     "script_started",
     "script_timeout_suspected",

src/Web/autopilot-monitor-web/utils/shared-manifests.json

@@ -499,6 +499,11 @@
     "ime",
     "realmjoin"
   ],
+  "sessionAnchorIneligibleSources": [
+    "SystemTimelineWatcher",
+    "WindowsUpdateWatcher",
+    "ServicingWatcher"
+  ],
   "ruleSubmissionKinds": [
     "gather",
     "analyze"
@@ -891,6 +896,7 @@
     "remote_config_fetch_failed",
     "script_completed",
     "script_failed",
+    "script_output_reconciliation",
     "script_recurrence_summary",
     "script_started",
     "script_timeout_suspected",