My dad was wondering the same thing. It doesn't make any sense!! It's really annoying too, Aston would have been easier to get to, as I live a 10 minute bus ride away, yet i'm having to go around the country with the other uni's that are backups!
But can you imagine how intensive an Aston interview would be? I met one of the pharmacy lecturers there on a biology thing for year 10's which i managed to smuggle into and he was already pressurising us and he didn't know i wanted to do pharmacy!! The labs are AMAZING though!!