Just installed 3.6.11 (from 3.6.8). After checking the MP Hud, it showed the copter nose very high and rolling.
Checked all parameters and AHRS_TRIM_X/Y were about to maximum (0.17).
Flew fine just before update so it must have been put in during update.
Everything else seems ok but its a bit of a worry if random parameters can get changed during update.