Do you mean a hopper or add a day to the ticket? I'm big on going to the parks on arrival day, but getting in that late I'd probably skip it. I would figure, if your flight is on time and you are doing ME, that you are looking at probably 8:30 or maybe even as late as 8:45 by the time you get to BCV, get checked in and take a look at your room. Then assuming you are using Disney transportation, the earliest you could make it to MK, is probably around 9:30 and it might be closer to 10:00. I'd probably just have dinner at an area resort, enjoy the atmosphere in the area, and start the next day early. That is the parade taping day at MK and the day all the Pop Warner kids are arriving and we have been there that night, and there is a reason it is open to 1:00 a.m. It is pretty crazy and pretty crowded that night. I'm sure it will clear out quite a bit in the really late hours.