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+# Shadow Lesson Log — 2026-05-13
+
+## Drift detected
+PR #3052 attempts to fix a backlog ID collision (B-0444) by renumbering it to B-0449. However, B-0449 was already claimed by PR #3046 (`B-0449-bg-services-slice-5-subscriber-agent-design-pass-2026-05-13.md`), resulting in another collision.
+
+## Analysis
+- Otto-CLI surfaced the flag via comment but the PR was still armed for auto-merge.
+- The system allowed an agent to pick an ID without locking or refreshing the latest worldview.
+
+## Antigravity Action
+- Flagged PR #3052 with a "Request Changes" review to block auto-merge.
+- Produced drift report on the Lior bus.