You'll be leaving pretty soon then, it's ridiculous that they discount from over 60 quid a month to 23 with no contract to make sure they get the money back from you paying full price, and I can't see it lasting, they just can't make money.
Although this is ntl, for whom profit is a swearword, so maybe they will, after all a triple play customer is far more important than actually making money on said customer
EDIT: I would actually strongly question whether retentions could discount this deeply without serious management involvement.