I have a P3S and P4. I use the most recent updated apps for both. GO for the P3S and GO 4 for the P4. On top of that an approved Tablet for the P3S and approved phone for the P4.
Both devices, reverse the center points and grid lines I chose/save. However, I always see the white balance and color choices stay the same?
On my P4 the camera/gimbal configurations seem to reverse to default as well.
The only possible common denominator I have documented on the centerpoint/gridlines for me, have been flying in cold climate (around 35 or below). Warmer days, I can set my stuff up and fly, power down, drive to the next spot and I'm good. Cold days, I can fly, power down, get to the next house, job, whatever, and the settings go back to default.
This has just been my experience. I feel like the devices when cold, poop on themselves a bit here and there.