I don't use JB often to commute but the agents at the "ask" desk in JFK are mostly helpful. Once I get off the plane from terminal 8, I get on the phone and make the mad dash to terminal 5. By the the time I get to the counter, 30 minutes have passed and I show the agent and I get listed with no problem.( this also requires some sucking up with the agents) the agents name is Belinda, always great even waiting behind a screaming pax.
Thanks to the crew like always, storing my bags in the front instead of having it go in the belly.