A guy on Fox was just suggesting this could be the result of a physical struggle over autopilot being turned off/on.
I’d be looking real close at the co-pilot. He’s was the right age to catch sudden jihadi syndrome.
Could be, going up to THAT extreme altitude that not even a flight simulator can do would serve no purpose except to kill the passengers, if there was some kind of struggle, what happened after wards, and how come the pilots didnt put in the hijacking code