Скачать или смотреть WLtoys F939 PoleCat gyroscopic stabilisation defect

Got a WLtoys F939 PoleCat from BangGood a few months back and didn't have time to fly it (too busy working on my drones or flying my other planes). This is supposed to be the newest and greatest from WLtoys, with gyro stabilisation.
On the maiden flight I tried a couple of hand launches but every time the plane went crazy and flipped out of control upside down and crashed into the ground.
Couldn't figure what was going wrong. Checked CG, controls on the remote, couldn't find nothing wrong. Until I had a look at the elevator. When the plane goes nose up, the elevator goes up as well, amplifying the error. When nose down, it also goes down, pushing the nose even further down.
So instead of stabilizing the plane, it does the opposite, it destabilizes it. All other control surfaces work as they are supposed to, the ailerons and the rudder, correcting the plane if it tends to go one way or another, but the elevator does exactly the opposite of what it should do, making the plane go berserk.
And unfortunately there is no way to disable this brilliant gyro stabilization, the plane is simply unflyable if I may say so, totally useless.
Trying to get the guys from Bang Good to do something about it, reimburse of maybe come up with a fix.