Pardon my level 2 English and indiscriminate use of "stuck". You're correct, of course. I didn't mean to imply THS was mechanically stuck at full nose-up position.
When the aeroplane started tumbling, control law went to direct, which has no autotrim, therefore THS remained in last position before law switching, as expected. However, once the gear was up, law went to alternate, which has autotrim (except abnormal alternate, that disables it while the aeroplane is tumbling, but restores it once it gets upright), yet the THS maintained extreme position. I keep my fingers crossed for investigators to find out why.