Slightly off topic sorry, but I also rang CS, moaning that as I now use VOIP for telephone calls, I wanted to cancel the phone, knowing that it's part of the TV package.
I was told I couldn't, so I suggested that I will cancel phone
and TV. They didn't want me to do that, (I also didn't want to do that!), and so as a result I now get £10.50 monthly reduction on my TV package, basically the phone line rental, and still keep the phone.