I'm surpised you were able to hit the stop at such a low altitude and warm OAT. I'm familiar with a slightly bigger PT6A (-67D), but have encountered the stop from time to time - always at or near FL250, in the dead of winter, SAT - 35C or so. The N1 redline for this engine is 104%, and the FCU stop under those conditions has yielded anywhere from 102-104.3%.