Phoned Sky who gave me an excuse they can only configure my line to 768kpbs downstream as BT have limited the "power" to the line?
What a load of rubbish!!

Check in your MySky page Broadband details and see if DLM is running on your line. It is being put on a lot of older lines and yours may be one of them. Either that or it ran some months ago during the trial and has left your line crippled. If it is not training, phone Sky and ask them to manually configure your line. If you don't get satisfaction on one call keep calling until you get someone with more than air between their ears. Your present stats show your line is capable of 4-5Mb with no tweaking of your internal wiring.

Alternately, use the KANA form to make a complaint and copy and paste your stats to the form so that CST can see it is capable of much more.

The main thing is not to give up.