Anybody knows how the interline luggages are handled on a CX J arrival from HKG-YVR-JFK, to an AA JFK-MIA?

I have scheduled ample connection time (because CX sometimes has hours delay due to weather in YVR from what I read) but no knowledge how the clearance of Immigration / Custom and interline luggages are handled as we normally fly the TPAC route to arrive West Coast but this time due to AA has no award seats LAX-MIA but ample inventory JFK-MIA so I opt this routing.