As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTOPILOT B DISENGAGE DURING CRUISE. UNABLE TO RECONNECT WHEN WE TRIED TO RECONNECT AUTOPILOT B IT DISENGAGED AND ROLLED TO THE LEFT. AIRPLANE APPEARED TO BE IN TRIM. (AUTOPILOT B WORKED FINE FOR THE FIRST 30 MINS OF FLIGHT) GROUNDED - YES. ON DEFERRAL.