diff --git a/WORK-QUEUE.md b/WORK-QUEUE.md
index 7e991d1..e25c36b 100644
--- a/WORK-QUEUE.md
+++ b/WORK-QUEUE.md
@@ -3988,3 +3988,47 @@ Not acceptable substitutes: re-verifying the served Helm page's FRESH/STALE stat
 `https://alexanderwhitestone.com/helm/` every tick, and the page's state is Alexander's §4 decision, not a lane
 unit), and any further digest of `recoveries/summary-fidelity-pilot.md` — that file is only what the
 alphabetically-last selection returns, and `MERCURY_CHECK_ARTIFACT` now sets the target deliberately.
+
+**Amendment, 2026-10-11 12:08Z (control plane, written from the tick that landed
+`replies/2026-10-11-to-mercury-02.md` at `d5a1798`) — the day-3 pin above is corrected: the Q25 negative
+control it pins has already been executed and recorded, so Mercury's day-3 unit is the first slice of Q31, and
+that slice is now executable rather than rhetorical.**
+
+The 12:04Z pin named the Q25 negative control as the one acceptable unit for the lane. It is not owed, and the
+evidence is in Q25's own deliverable rather than in a later item: `recoveries/prose-anchor-convention.md` §2
+carries the control in full — pristine build in the scratch tree → `Built 123 pages from 121 entries (121
+cleared, 0 research-only)`, `diff -rq` against the live `site-ledger` **silent**, tree digest
+`91ecf6bf939a2a49…` on **both** sides, 125 files (`:64-65`); the Q25 prototype (`build_blocks_proto.py`)
+against the unmodified `blocks.json` → the **same** digest, 125 files, byte-identical (`:80`); the shared tree
+re-checked after, untouched (`:94`). The positive leg is recorded too: the Q24 H1–H4 token demo changed **3 of
+125 emitted files** and no others. Q26 re-ran the same control with the hardened prototype (`f05179e`), and
+Q28/Q29 each copy and hash the hardened builder before any fixture. Nothing in that slice is left for a third
+party to add.
+
+The Q12 entry-page step the pin also carries ("owed from day 1") is settled by reference the same way: Q21
+fetched **all 121** entry pages, HTTP 200 on the first attempt, and Q22/Q23 re-derived their rows from those
+live pages rather than from Merlin's text; a fourth pass over 18 of 121 adds no evidence
+(`replies/2026-10-10-to-mercury-01.md` §6, which the pin cites while re-owing the work).
+
+**Where that leaves day 3 — the unit, and why it can be executed at all.** Mercury's unit is the first slice
+of **Q31** (the collector's entry point, the sibling path no gate has executed). This tick made that
+executable: the harness gained a real task runner (`/root/troupe-harness/mercury_standup.py` v2, 13,784 B,
+sha256 `217586b622a17088b784d9ff51fbc40017de7ee1dd86f2af1d335f8982a92c3e`), driven by
+`/root/troupe-harness/mercury-task.txt` (2,715 B, `40dcf28b…`) whose `run:` lines it executes with a 300 s
+timeout and hands to the model verbatim, plus a leak-free summary helper
+(`mercury-q31-summary.py`, 3,191 B, `b7977428…`) that prints state/freshness and never the snapshots'
+contents. The unit itself: the collector's two safe legs — `--dry-run` and an explicit
+`--out /tmp/mercury-q31/snapshot.json` — around the live snapshot's digest and mtime read before and after and
+a `find -newer` marker test, against `/root/.helm/bin/helm-collect.py` `ee0b36a8…` (27,907 B, mtime
+2026-10-11 09:06:15.259049023Z) and a snapshot frozen at `2026-10-08T17:12:59.475Z` / `aa842b0f…` / 14,039 B.
+The bare command is forbidden in the task file and refused by the harness guard; the first execution of this
+revision stays Mercury's. Full reasoning, the harness self-test and the grades:
+`replies/2026-10-11-to-mercury-02.md`.
+
+**What the day-3 pin got right, kept:** the lane's problem is not Mercury's arithmetic — the census reproduced
+three times, and this tick's re-run was byte-identical to the 2026-10-10T15:38:02Z index reading
+(`4f764ef4dfb9c08b…` / 34,488 B), which is the published-state fact worth having: **nothing has been published
+in the ~20 h since**. The problem was structural and it was the pipe's: v1's harness ran four fixed commands, so
+the lane could not land an artifact at all (§2.2 was unreachable for it), its digest fell back to the
+alphabetically-last file — the same unchanged file two days running — and `replies/`, where its units are
+assigned, never reached the model's context. All three are fixed in v2 and logged as mine.