Indie 6th form interview help

[Almostfinished15]

After a long wait for results, DD has found out she has an interview for an high-achieving Indie.
She took maths, chemistry, physics and philosophy (but wants to take IB at that school)
Any idea about what questions she'll be asked?
How should she prepare?

Is it just an interview, or is there also an exam?

If it's interview only, it will probably be a chat about general knowledge and current affairs. The offer will be conditional on her GCSE results.

If there's an exam, there will be stretching questions based on GCSE knowledge.

DD went for an interview this time last year. There were fairly detailed subject interviews with the HODs (approx 25 mins per subject) and a general interview with the HOY. The general interview related to her interests and out of school activities - however there was a lot of emphasis on what would she bring to the sixth form and what would she be able to contribute. Also, as it was a sixth form in a school, there was an expectation that she would be part of the school 'management' and not just a pupil. It was a good experience for her and she was given a conditional offer based upon the GCSE results.

At another selective local private sixth form there are exams - based on IGCSE syllabus as well as interviews. This sixth form also has boarding pupils and the interview/exam takes 2 days with an overnight stay.

It's just an interview - she took the exam at the beginning of November.
Thanks,