NTSB Posts Preliminary Report On Wyoming PC12 Crash

You are correct. By the time the autopilot hands you the aircraft it has moved one or more trims to one of their max extents and there is still too much force for the auto pilot to counteract. When it finally disconnects the aircraft will violently pitch and/or roll. The pitch is usually downward pinning anyone not buckled up and all loose items to the ceiling. If unexpected and IMC, good luck.