Different strokes for different folks.
When I was a cadet I didn’t take any time for studying, as I had a broad social life and was out most nights, so missing ‘cadets’ wouldn’t have made any difference in terms of a release from the grind of revision. However in my day it was exams like they have just moved back to, BUT the job market and benefits systems was geared to school leavers so further education wasn’t really needed and certainly not compulsory as it is now.
Take the time you feel you need. You’re 15 or 16 so need to start taking some responsibility for yourself and making decisions that suit you best. If you feel you need all the period of the exams take it, if it’s the night before take it or you feel you don’t need to, don’t. But it’s for you to decide and prioritise. People at schools, on here, and at the squadron will advise, but none of them are you.
Ultimately what you do in the ATC really has limited benefit to your future and while some of the other things you do in the Corps may (I say may) help you, it is insignificant compared to results of GCSEs, as these will provide you the means to access courses at 6th Form and FE Colleges and when all said and done a pay packet. Many A Level courses require a minimum B (or whatever the number equivalent is now) in a GCSE at that subject or linked subjects. Bearing in mind if it is a popular subject / course and there are limited places you need the higher grades. Whether this means more revision or concerted effort in school, only you know. Speaking as a parent who has had 3 kids go through this, we let them make the decisions when it came to outside activities and revision.
I found this year interesting as it was I think the first year proper of the new style GCSEs and I was surprised that more cadets didn’t do study leave. The irony is one cadet didn’t take any time off at all and got 2 9s, 3 8s, 3 7s 2 5s these were the best set of results on the squadron. Oddly they only needed a 4 in maths and English and a good pass in art to get onto the course they wanted to do and are doing. Another who started their study leave in April got a 2 7s and all the other subjects lower grades. So was the time off really an advantage?