I don't see why they wouldn't. A C is a pass and they can take into account you did it a year early.
EDIT: Just remembered, if you can't do it it's not the end of the world, you don't need to do law at A level to do it in uni (in fact it's an idea to not take it as you'll be doing mostly the same stuff)
Regarding your remark question, I believe if they remark it and you go up a grade it's free of charge.