Advice on how to connect fibre modem to router please

[#1]

Hi
I am upgradeing to fibre soon. My BT master socket is in the bedroom but my existing router is on an extension in the study. When I upgrade to fibre I have been told that BT engineer will fit the modem on the master socket but I want to keep the router in my study. There is 6 core telephone extension cable between master aned extension socket. Is it likely that I can use the 2 spare pairs in the telephone cable to connect modem to router or do I need to rip up floorboards so that I can run cat 5 cable to the study. Distance is about 10 metres.

[#2]

You have 2 choices.
Order the extension at the same time as the fibre, Then BT can move the modem to your router, but not under floor etc only along skirting board.
Do as you say install a 10-15m cat 5 cable between the router and the modem, under the floor as needed.

[#3]

Hi DrBob,
As Hairy Biker states you have those two options. If you wish to order the extension kit let me know and I'll arrange that for you.