I am still having an issue on the P6P, with the fingerprint sensor failing when AOD is turned on and in low power mode
Do this - lock the phone, let it sit for about 5 seconds, the screen will quickly flash when it enters low power mode. When attempting a fingerprint unlock in this state, it will say "press firmly on the sensor", followed by "fingerprint not recognized". Since this action "wakes up" the screen, the following fingerprint will unlock.
This is repeatedly reproducible and is not the actual fingerprint failing, but something to do with the screen being in low power AOD mode kicking back any fingerprint attempt. I can "wake" the screen or bring it to the normal lock screen and the fingerprint works 100% of the time. This is some bug introduced a few months ago (it used to work normally).