Vilas,
We were simulating at stall in level flight at 5000 feet. The levers were at idle. Auto trim worked until well into VLS but stopped well before Vsw (Alpha SW) on both the 380 and 330. The speed brakes auto retracted once we entered VLS in both the 380 and the 330. I don't know how else to explain it.
As I said, I have no clue if the mini buses behave differently.