Thanks man! If you're doing similar subjects to me I'd say enjoy your Summer and relax, I did look at some stuff during the Summer and forgot the bulk of it by the time I started learning
Lol. I've started C1. I'm now a Indicies expert.. I hope! :P
I'm really not the guy to ask as I didn't sit bio or Edexcel science. All I'd say is do all past papers on your spec twice if possible and make sure you know the entire spec.