Set this to match the region
GPS_GNSS_MODE,7
Also there is a Here4 update to do, but DO NOT do a UBLOX update!
This might have been what you saw - the Here4 can momentarily lose gps after 1 hour of use.
I couldnt see anything else wrong, except you need to set your correct battery voltage levels and failsafe actions. Unsure about other plane-related settings.