I have Googled this in depth, spoken with my ISP (zen) and BT (via call centre's abroad) and I still have no definitive answer, so if anyone can help, I'd be very grateful.
Like many people, my master socket is in an inconvenient place and I need the fibre installation placed at the site of an extension socket. The wiring is: Master socket has 2 extensions cables wired into it. One goes to a phone the other goes to my office with a phone and adsl broadband. So this is a star arrangement of extensions from the master socket, not a chain.
I want the office one to become the new master socket so that the VDSL modem and router can be sited in the only possible place.
The cable used for the office extension is termed “Telephone Cable 3 Pair 6 Core” (Screwfix product 17421). The run is 8m long. This cabling was only recently done into a new part of the house and I only wish I’d used cat5 or 6 and probably none of this would be an issue.
The question is: can the office extension be converted to a master socket considering it is connected to the current master with non-twisted pair cable?
If not, I can try to replace the cable run with cat5 by cutting the extension at the master socket and taping cat5 to the end and pulling it though along the same route as the phone cable (behind plaster board, into loft space and back down behind plasterboard). This is ambitious and may not work but it’s all I can think of to route the cable without holes in brand new walls.
Or I can ask BT to move the master by digging outside and changing the entry point into the house (expensive). Or I can ask the engineer when he arrives but he might say that it’s not doable and then I would have abortive install charges (85 +vat I'm told) as I can’t site the modem and/or router at the site of the current master and won’t abide the 30m extension offered by Openreach.
Please let me know the answer if you have one.