just a bump on this for anyone wanting refunds. ours has just been cancelled so i tried the 0161 number quoted previously and its not in use anymore. calling the number on the site said the numbers had changed also, and gave the new number.
the new number is 0330 5515 151. called that, option 1, had to listen to a few minutes of bumph but then not too long a wait to get through. only our flight out had actually been cancelled so as has been stated before, make sure you ask for BOTH to be refunded.
painless in the end, full amount refunded and should be processed within 7 days.