I got into Boston University, but

I got into BU but they told me I got in for the January 2016 entry and spend the summer in London for six weeks. This sounds great and all, and BU was a reach school for me, but is there any way I can call and see if they can waitlist me or switch me to the regular entry for the fall of 2015? Can anyone give some advice to what I should do? I just dont want to fall a whole semester behind the graduating class and my parents will feel like I’ll be wasting time in the fall.

I doubt they’ll budge. They chose that program for you for a reason and if they let you switch then they would have to let everyone switch.
I suggest that if you really want to go to BU, just take their offer and use the fall to work and save some money. Boston is expensive even if you’re wealthy. Also remember that you won’t be the only one in that program, so you’ll have peers that you graduate with in your class. If that really worries you though, you can always do a summer semester to catch up.