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Maths at Oxford

So I got AAABC at AS, with As in maths, further maths and computing. However, I only just got an A in further maths (by 1 UMS point) as I messed up in D2 (where I got a C) and the FP1 exam was harder than ever so I only just got an A in that. Therefore my teachers probably won't predict me an A* in further maths, which I need for the Oxford maths degree.
This year I'm dropping Physics as I got a C in it and I've already started my Computing coursework so I will have more time to focus on maths and resitting D2. I want to try hard to get A*s in maths and further maths but without this prediction would Oxford reject me (especially with the C in Physics)? I'm also considering applying to imperial and/or Warwick where again they want A*s in maths and further maths.