Originally Posted by
gwar69
All incoming bags from Canada get rescreened. You don't have to do anything, but it takes a little longer since the bags are brought to baggage claim, met inside by a ramp agent, and then taken over to the TSA. At 89 minutes you should be ok, just don't pack anything you need right away.
IIRC, the last time I flew from Toronto Pearson I was screened by a TSA agent and not CATSA (Canada's equivalent agency) once I had gone through CBP pre-clearance.