I've done B2B on many ships and many different ports. Can't remember any one being the same. My guess is since this is the a U.S. port, you will have to disembark, go thru customs/immigration, then reboard. You will be given your new seapass. Check out with the old, then check back in with the new one. It should be a simple process, but I would plan on having to get off the ship to some holding area, then reboard.