That's not true. You can check in at either. We arrived and the line was rediculous at the contemporary to check in due to the time we arrived. We went to the park since it was well before check in time anyway.... Came back around 3:30 went straight to BLT desk and checked there. You don't HAVE to go to contemporary just because you are dropped off there by DME
FYI... That was yesterday for us.