Compass Alignment(Arrow forward and flat mounting): Tilting the magnetometer is strongly discouraged ! INAV/BetaFLight: CW 270° Flip when flight controller arrow is facing forward also Ardupilot/Mission Planner: Rotation None
BF doesn’t support GPS position hold and RTH, GPS Rescue mode is supported by BF3.5 or last.
No need compass for Fixed wings with INAV firmware
The scratches on ceramic antenna are the result of tuning the antenna by ublox.
Make sure to have compass/magnetometer 10cm away from power lines/ESC/motors/iron based material