<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by BumpMe!:
UPDATE:
Called back after a shift change...
without any hesitation, a different agent changed it for me to include the LGA connection.
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You can book it, but it's definitely not pleasant. The shuttle folks won't check your bags through for you, so you'll have to grab your bags from the Marine terminal and carry them with you as you ride the bus all the way over to the main line terminal and check them in again.
Also, in case the mood strikes, don't try to walk to the Marine Air terminal from the mainline terminal---the sidewalk ends and you'll find yourself on the side of a very narrow high-speed road! (Yes, I found this out the hard way, and was very impressed at the kindness of the shuttle bus driver who pulled over ot pick me up. He must not have been a local!)