It was in 2012, but I flew YVR-JFK-SRQ (CX+B6) my bags were interlined by the CX agent in YVR. I did have to request this and show both PNRs and airport codes.
My connection time in JFK was tight, but the B6 flight was 1hr delayed so after clearing and rechecking bags, and then reclearing security, I made it with time to spare.