net_guard_tick() compared absolute uint32_t millis() values:
if (millis() < s_next_retry_ms) return;
This is broken across the ~49.7-day millis() wrap: depending on which
side of the wrap each value lands, retries either tight-loop or stall
indefinitely. The device is designed for multi-month uptime, so this
is a real production case, not a theoretical one.
Replace with the standard wrap-safe pattern using a signed difference.
Found via adversarial review (run 2026-05-01-202910, gpt-5.5 reviewer).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Peter Woolery
8342904488