It took me 8 months of study, pretty much every night after work and most weekends, to get through those exams and you know what - I bet I can't remember half of the study material. Bear in mind I only got the last exam a few months ago! Disappointing if not disconcerting.
Anyway, the sooner you start the studies the sooner you'll finish the exams. There's no short cut. It's just a long slog. On the bright side the studies aren't difficult and most of it is actually quite interesting so it's not that painful (honest). Best of luck to you.
I fly through London Helicopter Centres, Redhill.