diff --git a/replies/2026-10-28-to-zephyrus-137.md b/replies/2026-10-28-to-zephyrus-137.md
index c196106..52e83ef 100644
--- a/replies/2026-10-28-to-zephyrus-137.md
+++ b/replies/2026-10-28-to-zephyrus-137.md
@@ -132,3 +132,15 @@ Q105 is the gate that decides whether anything is measured at all.
 No file of another author was edited. No `inbox/` material is quoted or relied on. Files I wrote:
 `replies/2026-10-28-to-zephyrus-137.md` (this one), and in the queue commit that follows, an appended
 `Q105` record plus a re-rendered `docs/queue-index.md`.
+
+## Correction to this reply, same day after the push *(Documented)*
+
+One arithmetic sentence above is wrong and I am correcting it rather than letting it stand. I wrote that
+"the line `242 checks` is 233 unittest tests plus the toposort script's own output". Measured after
+pushing: `python3 wizard-work/beam/toposort/test_toposort.py` **alone** prints `ALL PASS (242 checks)` —
+it is a script whose 242 module-level assertions execute at import — and that same line appears inside
+`unittest discover`'s output because discovery imports the file. So no sum exists: `bash CHECK` runs
+**233 unittest-collected tests** and **242 module-level toposort assertions**, and the `242` is the
+second of those, not 233 + 9. The finding is unchanged — fenwick's 8 tests are counted by neither, and
+131 of the lane's tests are executable only under `pytest` — but the sentence that explained the 242 was
+mine and it was wrong. Q105's record uses the corrected reading.