Sunday-only spike: bad-call rate hit 10.14% (+0.97pp vs prior 4-Sun avg of 9.17%). Cross-platform, cross-version, all 12 monitored corridors moved. Signature: mid-call audio freeze + long connecting-fail (>2s).

Android silent-ring rate hit 18.96% on 2026-05-11 — the single highest day in the trailing 90 days (+1.60pp vs 5/8 baseline). All 11 monitored corridors moved the same day. Real Grafana data. Investigation tracked in PB.