Oh, that's a tricky one. I have no idea sorry. I'd give your current consultant a ring I think. It should be valid for any class but you have paid your consultant up front so it's her money if you know what I mean.
Saying that, if you didn't use your countdown this week then you would lose a week from it as all weeks off have to be booked up front.
So, hmm, that means you should be able to use it.
Waffle... sorry.... give her a ring!!