It may be helpful for those of you thinking of applying to realise that "to be competitive" it is usually recommended you need to have achieved A*A*A for Arts subjects and A*A*A* or better for Sciences/Economics.
Pooling used to occur only at A*A*A* (there are similar scores for Scottish & IB results).
All your UMS will count A2 & AS but your first sitting of AS will be used for ranking, not any resits after the first year of study.
Your best three subjects will be used for Arts, Best three for Sciences & maths for NatSci. Maths & FM count as one subject for a three UMS ranking but Maths/Physics is used for Engineering/Maths as an average of all module %. For Economics the Maths & FM is really important.
A UMS average of 92%+ for less competitive subjects up to 96%+ for the most competitive is the right sort of target.
It is not true that Gap years are unpopular with Cambridge or other universities. The success rate for Gap year students is almost the same as for A2 year students. There are obviously a mixture of reasons for applying-usually better results than predicted or unexpected rejection first time.
Maths is the least happy with re-applicants-you have to show you are keeping your maths up. Medicine in my experience was very common and a year spent working in a care home, in a charity or gaining more work experience was favourably looked upon. It is easier to get in as a Gap year student post-qual than it is to achieve a deferred offer in the first place.