In SW2021, interference detection is out of synch with collision detection

I just migrated my project from 2019 to 2021. Normally when I want to test range of motion I first do a top-level interference detection to make sure I won't be in a collided position. Then I do a move component with stop at collision enabled to find my range of motion.  

In 2021, however, I get "no interferences" and then immediately "the assembly started in a collided position" This seems wrong to me. Any advice would be welcome.

to replicate:
-load wing.saldsm
-confirm no interferences
-open move component, check interference detection and stop at interferences
-pull down on the knob at the bottom.
-observe error message