diff --git a/packages/dashboard/app/utils/taskRevert.ts b/packages/dashboard/app/utils/taskRevert.ts
index 4cbb37d4e5..957eba9ce2 100644
--- a/packages/dashboard/app/utils/taskRevert.ts
+++ b/packages/dashboard/app/utils/taskRevert.ts
@@ -94,9 +94,27 @@ export function findOpenUndoTaskForSource(tasks: readonly Task[], sourceTaskId:
     and the behaviour was the legacy fallback forever.
 
     Reverted rather than left as a dead seam. An unsupplied optional parameter is strictly worse than
-    the literal — the literal is at least honest, and the census keeps pointing here. Unblocking it
-    means hoisting the flags derivation above that call, which is a hook-ordering change in a
-    5000-line component (same blocker as the near-duplicate gate in that file).
+    the literal — the literal is at least honest, and the census keeps pointing here.
+
+    FNXC:WorkflowResolvedColumns 2026-07-30-20:50 (correcting the unblock recorded above):
+    HOISTING THE FLAGS WOULD NOT UNBLOCK THIS — IT WOULD INTRODUCE A WORSE DEFECT.
+
+    The note above says the blocker is hook ordering, i.e. a cost. It is not: it is a correctness
+    boundary. This function scans the `tasks` list for OTHER tasks pointing back at the source, so the
+    column it classifies belongs to a NEIGHBOUR. `detailColumnFlags` in TaskDetailModal describes the
+    MODAL'S OWN task, and its own FNXC note says so explicitly — it is guarded by
+    `detailFlagsAreForThisTask` precisely because using it for anything else is wrong.
+
+    So supplying it here would answer "is this neighbour finished?" with the modal task's traits: on a
+    project where two workflows reuse a column id, an open undo task would be classified by a workflow
+    it does not belong to and the affordance would vanish or persist wrongly. That is the flags-for-
+    the-wrong-row shape, and it is worse than the literal because it is wrong on data rather than
+    merely stale on vocabulary.
+
+    A CORRECT conversion needs per-NEIGHBOUR flags — the caller would have to resolve each candidate's
+    own workflow, which the modal does not have and should not fetch mid-render. Until a per-task lane
+    map is available at that call site, the literal is the right answer and the census entry is
+    accurate debt rather than a missed conversion.
     */
     if (candidate.column === "done" || candidate.column === "archived") {
       continue;