Surely only if there is a master elsewhere in the circuit? Or more precisely, if the incoming Openreach cable is connected to something other than this one? The incoming OR cable surely doesn't have these colours and construction? Or can it, and I have got it wrong?
If I'm right, then there must be at least three "sockets" in total, one of which may be an external NTE or the original NTE5A. The two sets of blue+blue/white, one of which could be the real NTE.
My theory ended up as there being an external NTE with the two cables we see being one from that and one to the extension.
But I have a feeling we have heard the last of the OP anyway.
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