As far as I remember, in BS1 I could press trim button, change direction, altitude etc. with pressed and then release trim. Without FD. Now, as soon as I press trim, bird jump up. Only way to fly "normally" is with FD on. And still sometimes occurs, that control became totally blocked. Even sending controls to all limits doesn't help. I didn't write about that issue jet. Had to test it more to figure out when it happens.