Trip Airfare I Just Went On Priceline.com And Found A Great Offer: Round Trip Airfare From New York To Washington Plus A?

I just went on Priceline.com and found a great offer: Round trip airfare from New York to Washington plus a? - trip airfare

Cars for just $ 284 (taxes included). The only problem is that it is not confirmed, said the departure. I can at any time of 6 hours between flights. and 10pm. Does this mean that I have to wait at the airport for 14 hours each way to be? "How does it work? No specific information on its website about how it works.