review(5 V2): flag stale rerun verdict race FAIL

machine-docs/REVIEW-5.md

@@ -149,3 +149,34 @@ I did **not** read `JOURNAL-5.md` before this verdict update.
   it that way posted a fresh `!testme` comment (`#13818`) and kicked off build `#35`.
 - This is a STATUS/HOW issue, not a new code defect. I notified the Builder via `BUILDER-INBOX.md` so
   the verification instructions can be corrected before the next claim.
+
+---
+
+## Cold-verify finding — 2026-06-01T03:22:00Z
+
+No `Gate: <Mn> CLAIMED` was pending in `STATUS-5.md`, so I used the idle slot for a fresh V2 rerun
+probe. I did **not** read `JOURNAL-5.md` before forming this verdict.
+
+### A5-3: `POST=1` can return a stale prior GREEN on a re-run of the same PR head
+- Probe target: `recipe-maintainers/custom-html-tiny` PR `#5`, head
+  `4bd8416a209f8521fdd804139c578156961633d3`.
+- Before invoking the helper, the PR had `BEFORE_COMMENTS=3` and the head SHA already carried an older
+  successful `cc-ci/testme` status pointing at build `#37`.
+- Cold-shell invocation:
+  `POST=1 MAX_WAIT=40 INTERVAL=5 /srv/cc-ci/.claude/skills/recipe-upgrade/testme-on-pr.sh custom-html-tiny 5`
+- Observed immediately from that single command:
+  - exactly one fresh trigger comment was posted (`AFTER_COMMENTS=4`);
+  - the helper returned:
+    `VERDICT=GREEN`
+    `BUILD=https://drone.ci.commoninternet.net/recipe-maintainers/cc-ci/37`
+  - That build URL was stale: it belonged to the previous successful run on the same SHA, not the run
+    just triggered by this new `!testme`.
+- Follow-up check ~40s later showed the live system had in fact started and reflected a new run for the
+  same SHA:
+  - `STATUS cc-ci/testme pending .../41 2026-06-01T03:21:30Z`
+  - `STATUS cc-ci/testme success .../41 2026-06-01T03:22:00Z`
+  - The PR result comment was updated to build `#41`.
+
+**Verdict:** FAIL for this V2 edge. Re-triggering `!testme` on an unchanged PR head can race against an
+older terminal commit status, causing `POST=1` to report the wrong run/result. Filed as
+`BACKLOG-5.md` item **A5-3**.