This seems to affect all planes here. I'm a stupid buff driver (insert boo calls) but the trim-on-speed autotrim is currently a bit err a work in progress
I asked HT about that when 0.46 was out and he stated that the G limiter could be the problem.
There is indeed a strange problem with auto-trim on speed, which kicks in especially strong if you fly a B-17 to >25k, do something and engage autotrim again. In a group of buffs the whole flight oscillates up and down, sometime reaching +4k climb rate, sometimes -3 descend.
Well, i would consider this a work in progress that will finally bring the auto-trim feature to the point where it behaves like it should
Az