Depending when you booked, you could still cancel your booking and get a full refund and re-book as it clearly states in their booking T&C's:
If you had not seen these terms and conditions at the time of booking and you do not wish to proceed with your booking now that you have seen them, please return all documentation to us or to your travel agent, within 7 days of receiving your confirmation invoice. Your booking will be cancelled and your monies will be returned in full, provided you have not commenced your travel
So you are entitled to receive a full refund upto 7 days after receiving your invoice (which takes at least a week to arrive in the post anyway if booking direct) so that gives you 14 days in theory from the day your made the booking.
Regards