In message ,
Tricky Dicky writes
Do not connect your router/modem to an extension socket on the phone
network it should be connected directly to the BT/Openreach master
socket with the shortest modem lead you can manage. Option 3 to me is
the obvious solution and rather than using cable with plugs on, use
Cat5e cable and two sockets with fly leads to the router and computer.

Limited knowledge alert.. don't you need to position your router where
you get best wi-fi transmission? All my visitors seem to expect good
links for their pads and phones!

I have a part used drum of cat6 you can fetch:-)

--
Tim Lamb