[Autopilot disconnecting]

I noticed that the disconnections occur at lower levels. On the flight in question, I started at FL310 and then climbed to FL350. There were simultaneous disconnections. Upon climbing to FL370, the disconnections stopped.

[Autopilot disconnecting]

The autopilot disconnected several times during the flight from SBGR to EDDF.

[Deterioration without effectiveness]

The deterioration bar is in effect.

[First 2 flights, both with FMC/flight path freezes]

It happened to me, flying to Australia, after hours of flying, the aircraft simply froze and went off, made a turn and apparently was returning to the departure airport, but I couldn't control anything anymore.