Consider this, as the last scheduled flight into Orlando arrives at 12:26 am, by the time they get those folks off the flight an onto the bus and delivered to their resorts, it is time to turn around and start picking up the folks scheduled out on the first flight of the morning which for May is at 6:00 am. (However, I have been on a 5:30 am flight).
Also, consider that they do track flight numbers and if a late flight is delayed till 1:00 or 2:00 in the morning, there should be "someone" there to transport you. At worst case, I've read about a sign on the desk with a phone # to call for transport.