diff --git a/RenderPipeline2.md b/RenderPipeline2.md
index 36e42db..0e5aa04 100644
--- a/RenderPipeline2.md
+++ b/RenderPipeline2.md
@@ -603,7 +603,8 @@ The server validates the manifest with Zod, cross-checks `shotId`/`shotCode`/fra
 
 **`source` (required from manifestVersion 2)** — the plate provenance the timecode check depends on (§8.1a). The panel resolves these from the *comp's own footage layers*, not by re-deriving paths, so the manifest records what was actually comped:
 
-- `timingPlate` — the element the comp's start time was anchored to (the panel's `primaryFootage`: longest duration, first on tie). A shot's elements routinely carry unrelated camera timecodes, so "the plate" must be named explicitly rather than guessed by the worker.
+- `timingPlate` — the delivered plate the render's timecode is checked against. A shot's elements routinely carry unrelated camera timecodes, so "the plate" must be named explicitly rather than guessed by the worker. **Only footage under the Footage Root qualifies**: a comp usually also holds pre-renders and CG passes of identical length, and anchoring on one of those is circular — it was rendered from this comp, so it can only ever agree with it, including when both are wrong. Among delivered plates, longest duration wins.
+- `frameStart`/`frameEnd` on a plate are its **own file numbering**, and are omitted when the filename carries no frame number. They are never filled from the comp's frame range: the render's first frame is in output numbering, so a comp-frame anchor skews the comparison by the gap between the two systems.
 - `startSource` — verbatim from the panel's existing start-frame resolution: `"footage metadata"` (probed from the plate, trustworthy) or `"API timecode …"` (fallback, suspect). This is known at queue time, so an export built from the API fallback can be flagged **before** it burns render hours.
 - `plates[]` — every element imported into the comp, for the record and for cross-element diagnostics.
 
diff --git a/RenderWorker/VFXReviewWorker.Tests/ExrHeaderTests.cs b/RenderWorker/VFXReviewWorker.Tests/ExrHeaderTests.cs
index abefa23..11e9b0b 100644
--- a/RenderWorker/VFXReviewWorker.Tests/ExrHeaderTests.cs
+++ b/RenderWorker/VFXReviewWorker.Tests/ExrHeaderTests.cs
@@ -100,7 +100,13 @@ public class ExrHeaderTests
     [Theory]
     [InlineData("UNG_102_019_010_cmp_TT_v005.01001.exr", 1001)]
     [InlineData("UNG_108_030_010_cmp_TT_v003.01204.exr", 1204)]
+    // AE-written renders separate the frame with an underscore, and turn up as
+    // layers in a shot comp alongside dot-separated delivered plates.
+    [InlineData("UNG_110_030_010_PRERENDER_01001.exr", 1001)]
+    [InlineData("UNG_110_030_010_render_1001.exr", 1001)]
     [InlineData("no_frame_number.exr", null)]
+    // A version suffix is not a frame number.
+    [InlineData("UNG_110_030_010_BG01_TT_v001.exr", null)]
     public void ParsesFrameNumbersFromFilenames(string name, int? expected)
     {
         Assert.Equal(expected, SequencePattern.FrameFromName(name));
diff --git a/RenderWorker/VFXReviewWorker/VFXReviewWorker.csproj b/RenderWorker/VFXReviewWorker/VFXReviewWorker.csproj
index 8bb313f..76fb9d7 100644
--- a/RenderWorker/VFXReviewWorker/VFXReviewWorker.csproj
+++ b/RenderWorker/VFXReviewWorker/VFXReviewWorker.csproj
@@ -15,7 +15,7 @@
       every change that gets published. publish.ps1 appends the git SHA via
       SourceRevisionId, giving "1.1.0+feb1c7b".
     -->
-    <Version>1.2.0</Version>
+    <Version>1.2.1</Version>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/RenderWorker/VFXReviewWorker/ValidationStage.cs b/RenderWorker/VFXReviewWorker/ValidationStage.cs
index f124177..2e41db2 100644
--- a/RenderWorker/VFXReviewWorker/ValidationStage.cs
+++ b/RenderWorker/VFXReviewWorker/ValidationStage.cs
@@ -409,7 +409,12 @@ public sealed class ValidationStage
             var header = File.Exists(local) ? ExrHeader.TryRead(local) : null;
             if (header?.Timecode is not null)
             {
-                var frame = SequencePattern.FrameFromName(Path.GetFileName(local)) ?? timing.FrameStart ?? m.FrameStart;
+                // The plate's own file numbering, never the comp's frame range:
+                // the render's first frame is in output numbering, so anchoring
+                // on a comp frame skews the comparison by the gap between them.
+                var frame = SequencePattern.FrameFromName(Path.GetFileName(local))
+                            ?? timing.FrameStart
+                            ?? renderFirstFrame;
                 return new TimecodeReference("manifest", local, header.Timecode.Value, frame, handleFrames);
             }
             _log.LogWarning("Timing plate from manifest is unreadable: {Path}", local);
@@ -589,7 +594,12 @@ public sealed class SequencePattern
     public string Extension { get; private init; } = ".exr";
     public int Padding { get; private init; }
 
-    private static readonly Regex FrameInName = new(@"\.(\d{2,9})\.[A-Za-z0-9]+$", RegexOptions.Compiled);
+    // Delivered plates separate the frame number with a dot
+    // ("..._BG01_TT_v001.01001.exr"); AE-written renders use an underscore
+    // ("..._PRERENDER_01001.exr"). Both appear as layers in a shot comp, so
+    // both have to parse — a plate whose number cannot be read gets anchored on
+    // a fallback, and a wrong anchor silently skews the timecode check.
+    private static readonly Regex FrameInName = new(@"[._](\d{2,9})\.[A-Za-z0-9]+$", RegexOptions.Compiled);
 
     public static SequencePattern FromOutputPattern(string outputPattern)
     {
diff --git a/VFXReviewConnector.jsx b/VFXReviewConnector.jsx
index 03d98bc..534e4ed 100644
--- a/VFXReviewConnector.jsx
+++ b/VFXReviewConnector.jsx
@@ -32,7 +32,7 @@ var SETTINGS_KEY   = "cfg";
 // Bump on every change deployed to a workstation. The panel reports this to
 // the server on load, so Pipeline → Machines shows which version each machine
 // is actually running and flags the ones left behind.
-var PANEL_VERSION = "2.2.0";
+var PANEL_VERSION = "2.2.1";
 
 (function VFXReviewConnector(thisObj) {
     var uiState = {
@@ -3701,9 +3701,32 @@ var PANEL_VERSION = "2.2.0";
         return plates;
     }
 
-    // The element the comp's timing came from: longest duration, first on tie —
-    // the same rule buildShotFromCode uses to pick primaryFootage.
+    // The element the comp's timing came from.
+    //
+    // Delivered plates win over anything else in the comp: a shot routinely
+    // contains pre-renders and CG passes of exactly the same length, and using
+    // one of those as the timecode reference is circular — it was rendered from
+    // this comp, so it can only ever agree with it, including when both are
+    // wrong. Only footage living under the configured Footage Root is camera
+    // material. Among equals, longest duration wins, as buildShotFromCode does
+    // when it picks primaryFootage.
     function pickTimingPlate(plates) {
+        var root = normalizeSlashes(trimText(CONFIG.footageRoot)).toLowerCase();
+        var delivered = [];
+        var i;
+
+        if (root) {
+            for (i = 0; i < plates.length; i += 1) {
+                if (normalizeSlashes(plates[i].path).toLowerCase().indexOf(root) === 0) {
+                    delivered.push(plates[i]);
+                }
+            }
+        }
+
+        return pickLongest(delivered.length ? delivered : plates);
+    }
+
+    function pickLongest(plates) {
         var best = null;
         var i;
 
@@ -3712,23 +3735,30 @@ var PANEL_VERSION = "2.2.0";
                 best = plates[i];
             }
         }
-
         return best;
     }
 
-    function toManifestPlate(plate, frameStart) {
+    function toManifestPlate(plate) {
         var ref = { element: plate.element, path: plate.path };
         var parsed = parseFrameNumberFromPath(plate.path);
-        var start = parsed !== null ? parsed : frameStart;
 
-        ref.frameStart = start;
-        ref.frameEnd = start + Math.max(0, plate.frames - 1);
+        // Only ever the plate's *own* file numbering. When the name carries no
+        // frame number the field is left out entirely rather than filled with
+        // the comp's frame range — those are different coordinate systems, and
+        // a wrong number here silently skews the timecode comparison by the
+        // difference between them.
+        if (parsed !== null) {
+            ref.frameStart = parsed;
+            ref.frameEnd = parsed + Math.max(0, plate.frames - 1);
+        }
         return ref;
     }
 
-    // "UNG_102_019_010_BG01_TT_v001.01001.exr" -> 1001
+    // "..._BG01_TT_v001.01001.exr" -> 1001, and "..._PRERENDER_01001.exr" -> 1001:
+    // renders written by AE separate the frame number with an underscore rather
+    // than a dot, and both turn up as layers in a shot comp.
     function parseFrameNumberFromPath(path) {
-        var match = String(path).match(/\.(\d{2,9})\.[A-Za-z0-9]+$/);
+        var match = String(path).match(/[._](\d{2,9})\.[A-Za-z0-9]+$/);
 
         if (!match) {
             return null;
@@ -3791,12 +3821,12 @@ var PANEL_VERSION = "2.2.0";
         timingPlate = pickTimingPlate(plates);
         if (timingPlate) {
             manifest.source = {
-                timingPlate: toManifestPlate(timingPlate, frameStart),
+                timingPlate: toManifestPlate(timingPlate),
                 plates: [],
                 handleFrames: CONFIG.handleFrames
             };
             for (i = 0; i < plates.length; i += 1) {
-                manifest.source.plates.push(toManifestPlate(plates[i], frameStart));
+                manifest.source.plates.push(toManifestPlate(plates[i]));
             }
             // Only claim a start source when this session actually resolved one
             // for this shot — an AEP opened from disk has no such history, and a
@@ -3805,7 +3835,8 @@ var PANEL_VERSION = "2.2.0";
                 manifest.source.startSource = buildState.lastStartSource;
                 manifest.source.startFrames = buildState.lastStartFrames;
             }
-            diagLog("manifest plates: " + plates.length + ", timing plate " + timingPlate.element);
+            diagLog("manifest plates: " + plates.length + ", timing plate " +
+                timingPlate.element + " (" + timingPlate.path + ")");
         } else {
             diagLog("no file-backed footage found in " + comp.name +
                 " — the render's timecode cannot be checked against a plate");