Resitting an A-level after leaving college, when can I apply?

I left before the summer just gone, i'm now at another college studying for a Foundation Art and Design and I just sent of my UCAS application the other day for University.

However, i'm now thinking i'd like to maybe do a couple of resits.
Is it too late to apply for January resits? I imagine it is, but thought i'd ask.
If I want to apply for June resits, when would I apply? And would I have to go to my old college to do that?

Also, due to only sending my Ucas off a couple of days ago is there I way I could change it to show i'm doing a couple of resits?
But am I only allowed to change it once im officially in for resits? because obviously if i'm applying for June resits I won't go and apply for them for quite a while.

I want to do a resit for Classics, thats quite straight-forward, but say I wanted to resit a module of a subject such as Graphic Design, which usually last a couple of months and has no exams, how would I go about that? And is that even possible?
When would I apply for that if it is possible? As it wouldn't be like applying for a particular date and exam. Because the Modules just start within the year sometime, and run for a couple of months, with no exams. There's usually 2 modules a year, so they'd start at the beginning and half way through the year.

Thanks for any help