Edit 9th of July, 2024: All should please update your Here4 unit using Mission planner DroneCAN/UAVCAN panel, select download from the internet. Software Version should be 1.14.FE92DFEF or later. DO NOT UPDATE UBLOX FIRMWARE
This fixes an issue that can cause momentary loss of gps after 1 hour of use
Edit: 3rd of July: Flight status RESTORED. After much testing, it is confirmed that the failure mode is 100% predictable, and if it happens in flight, Ardupilot has no issues handling this. Testing with the here4 as a flight controller with no other assistance is underway, and we will update on the tests asap
Thanks to @sidbh and Paul Riseborough for their efforts in devising the tests to verify return to flight status.
This doesn’t mean your mag will not fail, but it does mean that if it happens in flight, it by itself will not be the cause of an accident.
This has occured to less than 0.1% of units.