Hi Griff,
A site visit is mandatory as the master socket faceplate arrangement is changed.
Furthermore the engineer has to attach a tone generator to your line at the test socket so he can find your twisted pair jumper in the PCP Green Cabinet birds-nest.
Once he has cut your jumper and (hopefully) connected both ends up to the same colour pairs in both link cables, he will return to your house to test the service with his JDSU tester before commissioning the modem etc.
You are strongly advised to take photographs (if allowed) of the JDSU screens in case you fall into the bald_eagle1 quagmire.
(Well something about mire comes into it !)
Kind regards,
Walter