Hello,
This is such an interesting discussion, thanks.
I only would like to add some information: Especially in Arts, Access to HE courses are widely accepted, even by Russell Group members (Cambridge, for instance), providing that the required results have been achieved; the UCL, in contrast, is strict in its interpretation of Access to HE courses (they reject it at all).
Oxford, for example, could make conditional offers to persons who complete(d) Access to HE with 45 level 3 credits at Distinction + the compulsory GSCE in Mathematics or equivalent, A grade(s).
If one preferred to study sciences, an A-Level in Mathematics should be taken into account, if not achieved quite recently. Access to HE (Science) + an A grade in A-Level Mathematics. Other universities could be more open in this regard.
It is not necessary to choose one of these universities, however, they are the perfect standard, in my opinion.
(P.S. Sorry for my English, I am from Germany)
Best wishes