Even on modems which are locked down the lights usually change to show if DSL signal has been lost

In reply to a post by thesmileyone:

�the engineer I spoke to�said that the green cabinet 750m away was saturated�so they are "splitting" our connections to make room�

My best guess: They�re �pair stealing�. Depending on their age, your houses were probably wired with two pairs from the get-go, to make it easy if a resident ordered a second line. Some or all of those probably connect all the way back to the PCP (although they probably don�t continue on the E-side).

If I�m right, those redundant pairs are now being re-purposed for the new houses, by disconnecting your spare pair at the DP and splicing it to a new multi-core cable that runs to the development. So if you or your neighbour were to order a second line in the future, Openreach would need to find a spare D-side pair at the DP to reconnect it.

Of course, second lines are increasingly rare, given that people don�t much use fax machines, etc.