I think that on balance whilst I would be more than a little irritated at having to pay more per month to continue receiving the Discovery channels I'd rather that than lose them entirely.
That being the case, I say this as someone who is in the early days of a new TT contract so jumping ship to BT - whilst very much an option - would be an expensive one.
If this weren't the case & we were out of contract we'd already have done the deal & signed with the opposition by now though.