diff --git a/devlog/_plan/260909_spark_short_quota_attribution/000_plan.md b/devlog/_fin/260909_spark_short_quota_attribution/000_plan.md
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rename from devlog/_plan/260909_spark_short_quota_attribution/000_plan.md
rename to devlog/_fin/260909_spark_short_quota_attribution/000_plan.md
diff --git a/devlog/_fin/260909_spark_short_quota_attribution/090_closeout.md b/devlog/_fin/260909_spark_short_quota_attribution/090_closeout.md
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+# closeout (recorded 2026-09-09)
+
+Landed via #4128 MERGED (`b2142586a`, merge commit `91db6c2f2`, both ancestors of origin/dev);
+issue #4122 CLOSED. Remote CI on the exact head `b2142586a` was green: 28 successful check runs,
+0 failures, 2 skipped by their own matrix gates (`macos control`, `windows ${{ matrix.shard }}/6`).
+
+Delivered exactly the `000_plan.md` file-change map: the optional routed-model hint on
+`parseUpstreamQuotaHeaders` / `applyAccountQuotaFromUpstreamHeaders`
+(src/codex/quota.ts:411-538), all four `src/server/responses/core.ts` write paths plus the six
+`codexWsQuotaObserver` factory call sites, the compact path
+(src/server/responses/compact.ts:1018), and the four regression rows in
+tests/codex-integration/codex-quota-parser-parity.test.ts.
+src/codex/quota-auto-refresh.ts stayed unchanged as planned.
+
+Carried forward, not regressions:
+
+- Already-polluted account entries keep the stale account-level `short*` tuple until the six-hour
+  hydration TTL expires them on disk, or until a restart or a genuine non-Spark short write
+  replaces them in memory. Declared out of scope in the `000_plan.md` non-goals and unchanged by
+  the merge.
+- A Spark-saturated account is no longer preemptively avoided for Spark-routed requests, because
+  routing evidence reads only the account-level slot (src/routing/quota.ts:40-61). Bounded to
+  Spark requests and absorbed by the existing 429 pool rotation. Spark-aware exhaustion sourced
+  from `customWindows` remains a follow-up.
+
+The unit was committed into the product PR rather than kept separate; moving it here is that
+correction, made after the merge closed the unit.