Success, finally managed to get my last refund :-

27th Nov 2012 - requested refund via online form
26th Jan 2013 - Called executive club, told all they could do was submit the form again on my behalf, which they did
10th Feb - Opened case with customer relations. Told they can't do anything and to call executive club
18th Feb - Confirmed with customer relations that they really can't do anything!
26th Feb - Emailed Keith Williams hoping to get his executive team involved
18th March - contacted Diamond club via online form (never got a response)
30th March - random letter received from refund department to say that no refund is due on a ticket number that I don't even recognise.
4th April - Response from Keith William's office apologising, 10,000 avios compensation and to say cheque is in the post
19th April - Contact Keith William's office again to say I still don't have a cheque
19th April - Keith William's office respond that there is a delay and it may take 4 weeks
22nd April - Cheque received