What sort of commitment of time are you looking at for the orchestras?
If (a big 'if' that one) i get to Cambridge I would love to get involved in an orchestra. I'm about grade 7ish trombonist. My school takes music pretty (very) seriously, and although our orchestra is good, and ive done a lot of brilliant, challenging music with it, it takes up a heck of a lot of time - am wary of signing up to something that could take over my life!