The first option.
Get the modem on the line as soon as you can. Going up and across the loft will mean the cable passes light fittings which could include various fluorescents, CFLs, LED, 12v halogens and transformers &c all of which can generate noise. Ethernet will not normally be affected but VDSL (FTTC) will be.
You may want to try and get the OR Tech to move the master slightly within the room if it will make it neater.
Install a standard backbox with two RJ45 sockets on the face plate close to where the modem will be. Run two (2) Cat5e cables to where you want the Router and install another pair of sockets there.
When FTTC is installed, use a short patch lead from Modem to socket then at the other end another patch lead to the router's WAN input.
Add another patch lead from a LAN port to the second socket - that will then give you an active network port in the living where you could plug in a lap top or a SMART Television.
M H C
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