Galeon,
It seems that none of the 'girls' has anything to say on this subject.
I therefore accept what my BT source told me; The telephone line monitoring is only between the STU and the local exchange.
This means that Redcare lines are therefore not as well monitored as some people might imagine.
My source also tells me that Redcare was only developed because BT were determined to squeeze some extra income from the growing intruder alarm communicator market some years ago. Evidently, they were aghast that all they were getting out of it was a telephone line and rental. So they developed a service that provides a minor enhancement that only they could provide and charged royally for it!
I've heard that Redcare, percentage-wise against cost, is BTs most profitable part of their business.
I've always thought that it was extremely overpriced, but that is obviously what happens when someone has a monoply on a product/service! A bit like British Standards!