Geofences could be drawn but not removed. VesselAPI Hormuz dots vanished
on restart and DVR skipped between the 5 daily polls. Sentinel-1 re-hit
STAC on every pan and often painted a neighbouring swath. Executive
briefs truncated; ticker stayed empty unless something was critical.
- Layer-panel list + polygon popup DELETE /api/geofences/{id}
- Persist VesselAPI polls to vessels (UTC-day purge, DVR as-of, boot hydrate)
- Cache Sentinel-1 by 2° cell; pick covering scene; clip Leaflet tiles
- Retry truncated LLM JSON; ticker falls back to medium/low; 3-min HUD poll
