I am trying to book a flight from CLT to BOS with a connection in Boston to a Cape Air flight. I have flown Cape Air many times and know that the aircraft have only 9 passenger seats, thus no first class; however, I would like to purchase first class from CLT to BOS. When looking at flights, only main cabin is offered. Can you purchase the flight, selecting main cabin, and then upgrade to first class via Delta.com for the Delta portion of the trip? Thank you!