Flying this morning, on boot, the camera did its usual wobbly thing, got the tones indicating all okay, then after a few seconds, the camera went to point down.  Did this on 3 successive power cycles, then finally worked correctly.  Flew.  Swapped batteries, same thing for one boot-up, then okay after that.

Any ideas?  Power-up sequence is: RC, drone, app (with phone cleared of all other apps).

Wow. I know there is a setting in the GO app that will allow you to set the camera facing forward or down at startup.
But this sounds weird.

does it turn back to 90 degrees when you set the "camera down/forward" setting on your C1, C2 buttons?
If not try to do the gimbal calibration

Had the same problem, it progressively got worse. Returned it to BestBuy on day 15, second P3P worked perfectly. The other problem with the first P3P was when the camera initiated pointing forward (which was less and less), it would make a clicking noise while sitting idle, the new one does not make the ticking noise. It's the same noise when your PC is plugged into the USB port for looking at flight records (not the camera USB port). Also the problem P3P would loose the video feed intermittently and the RC was only a few feet away. Again the new P3P never has any of these issues.