EDIT: Drone flipped at takeoff. We followed DJI motor numbering, which is not correct according to the Copter motor numbering. Switched motor 2 and 3 and everything
Oh lordy. By reading similar issues in this forum I realized something. All along we have faithfully followed the motor numbering from the DJI manual. That setup is not the same as the Copter motor numbering. Motor directions are the same, but motor 2 and 3 are switched. Will have to replug tomorrow, hoping for the best.