I believe so. And yes, NTL/Telewest is cable.
If it had been landline it should have been feasible. As cable I reckon that's why no "usual suspect" can do it.
At least if it can be done, the people that know how may be able to help, and the ones like me that aren't sure will stay out of the way. Without knowing it is cable you could have been deluged with a lot of well-intended useless help.
Any service provider you ask probably needs to know as well.
My broadband basic info/help site - www.robertos.me.uk
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