transfer at JFK is no hassel at all, you will arrive into the B gates if you are travelling on the 105 or 111 where u collect ur bags head out and take a right into the transfer hall, there will be a lovely lady waiting on you there who will give u your boarding pass is you havent already got it at DUB and take ur bags, head upstairs and get the airtrain which goes on track 1 the right hand track and the next stop in T5 Jet Blue, and head in there for you connection, simple as. I only know cos i used to work there for EI. people fret about it but it is no hassel at all. if in doubt as the agent at the transfer hall and she will direct u to the airtrain