Thanks from what I understand unless you need to change terminals you stay in the secure area for connecting flights
I think it was that way pre covid
it would be all on one ticket so no need to check in again
This would be our transfer info
https://www.torontopearson.com/en/connections/guide?arrivingairline=aca&arrivingdestination=mia&departingairline=aca&departingdestination=yxu