Do I have to ask unis to drop my 4th A Level (S6)?

So I'm studying Maths, Further Maths, Physics and Classical Civilisations, and did a Programming EPQ last year (guess the odd one out lol). I would like to drop ClassCiv coming up to halfway through January, on the premise that I could spend my time so much more productively in extra reading, preparing for my A levels, STEP exams and programming and stuff.

I am applying for Mathematics, and the unis I've received word from so far are asking for A*A*A in Maths and Further Maths and anything else, so Physics works for that.

Do I need to ask the unis for permission to drop my fourth A Level? I'd honestly rather drop it than just take it and not revise for it, since that would also free up a solid 6 hours of work-time at school per week spent not being in a ClassCiv lesson...

Unless your offer is specific to you getting a grade in classic civ then you don’t need to tell them, but just in case you should ring the unis up

Who would I actually have to call?

Who would I actually have to call? I haven't had to do any inquiries about this sort of thing, so I am not really sure which department I should call. Would it be the Admissions department, or is there some other one?

Unless your offer is specific to you getting a grade in classic civ then you don’t need to tell them, but just in case you should ring the unis up

You MUST tell universties if you drop a subject - your application is not accurate otherwise.

If I do 4 subjects, and the offer is A in maths A in chemistry and an A in another subject, and I drop one of my subjects that isn’t maths or chemistry, I wouldn’t need to inform them am I wrong?