Anyway, I'm not too sure if it's worth studying Music at University. This is definetely a career that I want to follow, I've wanted to be a working musician for as long as I can remember, but what opportunities are on offer for uni graduates? I'm finishing up my Level 3 Diploma and I am able to teach guitar. I have also had auditions for function gigs. Presumably I could work for The Birmingham Music Service too, once my gradings are sorted out. So what exactly are the benefits of studying Music at uni? I'd love to go but I'm really struggling to see the benefits as I am able to work in this field without a Degree.
I'm currently applying for music at university and hold offers from 4 top UK universities. First, look at courses that accept a Level 3 Diploma. You should consider taking the A-level course as it will open up more academic courses at university (I assume that is what you mean by 'university')?
Alternatively, if your performance is good enough you could apply to conservatoire (eg Royal Academy, Royal College, Royal Northern College, LIPA etc). I personally didn't choose this option as I'm not Grade 8 Distinction and only picked up my main instrument relatively late (age 11/12) but it could be an option for you, especially if you are looking at the less competitive conservatoire (there are loads more than Royal Academy and RCM!!).
You could also look at some access/vocational courses or foundation years which would be better suited to BTEC/Level 3 Diploma/things other than A levels. Or you could look into getting placements, if practical work is what you're after.