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+| 2026-05-15T13:49:00Z | claude-opus-4-7 | 596e842c | shard: 2nd Copilot cat-n P0 false positive on PR #3485 cleared | (PR #3489) | recurring-FP class |
+
+# Tick 1349Z
+
+- PR #3485 (1343Z shard): SECOND instance of the cat-n line-number Copilot P0 false-positive (claim `1 ||` line 1; actual file byte 0 is `|`). Identical to the catch documented in PR #3483 shard 1340Z. Now a recurring class.
+- PR #3488 (1345Z shard): wait-CI, 0 threads.
+- Pattern observation: Copilot reads files in cat -n format and at least sometimes misinterprets the line-number prefix `1<TAB>|` as content `1 ||`. The error rate doesn't appear correlated with file content; expect this to recur on tick shards (1-line pipe-row at line 1 is the trigger).
+- Cron sentinel `596e842c` armed.