Attitude shift in diffrent modes

So I just tried to play around with Plane 4.01 on a test bird and had an interesting issue. When I would switch from Manual (default mode) to Qstabilize the attitude displayed on MP would shift drastically from a zero roll, zero pitch (the actual orientation) to a nose-down 35deg, and wings level attitude. Switching back to the manual would revert the attitude to nose level. This was with the same parameters that I had on when using Plane 3.9.10, and a rollback to 3.9.10 showed this issue was not present under the same conditions. Any clue as to what might be happening here?