I have to admit that until I was talked through dismantling the socket on Wednesday, I had no idea the test socket was there. But presumably, as the outer socket is provided by BT, they'd replace it free of charge.

And taking the outer socket off was not exactly easy. Firstly, none of my crosshead screwdrivers were exactly the right size. Then, the modem/hub was in the way so I couldn't get a clear shot with the screwdriver, and the wires and position of it made it difficult to get it out of the way. And I was still trying to talk to BT on my mobile at the same time.