It’s changed and by the fact they call it INS (and not UCSIS, changed in 2003) makes me think it happened a while back.
I know way back, TN visa holders got no grace period once dismissed from a job. Unofficially it was “24 hours”, and Canadians could always turn around and come back as a tourist to clean up, but that’s a huge kick in the teeth to someone you just fired.
