Good luck to all with January interviews.
The burn out is not surprising. There are so many hurdles to the medicine application, academic work is gathering pace, plus responsibilities from being at the top of the school. DD had her three interviews in March in the same week three pieces of coursework were due, and just after mocks, so did not do much prep. I bribed her to read a short book on ethics so she had covered the ground, though her extensive watching of TV medical dramas meant she was aware of the ethical questions behind standard plot lines. If not taking maths A level you might have a quick run through statistics and percentages. Two of her interviews involved overnight stays, so we took the iPad up and she read everything on the medical school website and was able to tell me over breakfast the advantages of both the course and University. (Intercalation options are a quick way to see what the University is good at - lots of public health in Birmingham.) She might had done more on the NHS structure but from what she has said, interviewers in part approached this by asking about what she had observed during her shadowing. I don't think interviewers had access to her PS at any of her interviews, but worth rereading it if only that you can repeat bits in interview.
She thinks she failed the ethics station at Kings, where they used vocabulary she had not come across so was unable to access the question. A course may well have helped. However her thinking was that yes she could have done more but part of why she would make a good doctor was her ability to remain balanced and level headed. If medical schools only wanted people who had devoted their final school years to their medical school application, spend months practicing UKCAT and interview prep questions, then perhaps it was not the career for her.
She got the other two, but in fairness she is happy talking to adults. Not least because of the work experience, volunteering and extra curricular she had done. She actually enjoyed the interviews. But perhaps because by then, when just about all her peers had offers, she had decided it was all in the lap of Gods.
It was a tough year. In contrast she is having a ball during her gap year. She only realised she wanted to defer after she had received her offer, but it was absolutely the right decision.