I phoned Sky a couple of months ago and told them I wanted to cancel as I could get it a lot cheaper with NTL. They told me that the £30 was only for a few months and then I would end up paying even more than I was with Sky.
The lady I spoke to said the only thing she could do was change my package to try and make it a bit cheaper.......
I told her that I would have a think about it and ring back later. I phoned later that day and went through the same routine as before but I said that I wasn't prepared to listen to them and I wanted to cancel. The lady I spoke to said she couldn't cancel it but I would be put through to her supervisor who could...
As soon as I spoke to the supervisor he offered to half my subscription for a whole year

....£21.50 instead of £43.00.....So I decided to stick with sky.
Yes Andy it does work to complain some times
Allan