We have a flight into JFK from LHR in July on BA. It is scheduled to land at 3:50PM. I used miles for this flight. Now I need to get a ticket to fly home from NYC. It looks like JFK is pricey for domestic flights, LGA is much more reasonably priced. Question: Is it doable to fly into JFK at 350pm and catch a flight from LGA at 750PM? That gives us 5 hours. Can we check in our baggage at JFK, or will we need to go through customs, get our luggage, transfer to LGA and check luggage in?