Hi SJA, I had this plane and the same issue.
Here's the mistake you making, you trimming the plane in safe mode.
Safe mode naturally has elevator up and a bit of right rudder.
Solution.
Put the planes trims to 0 on everything.
Manually adjust your control surface to exactly level.
Do not change any trims.
Put the plane perfectly level on a flat surface, bind the plane.
Before flying, put the plane on a flat surface, it does the little control surface dance.
Take off and switch to expert mode.
hold throttle at 50% exactly. ( Be sure that your ESC is calibrated.)
Trim the plane.
Land, put the plane off.
This will be saved forever
Make sure the plane is 100% level when binding.
Make sure the plane is 100% level when turning the transmitter on.
99% this helps.