Thanks for the info about the router. Sorry, I didn't make it clear about the devices and powerline adapter.
Devices: I was referring to wi-fi connections, i.e. mobile phones, ipad, security cameras. printer.
Powerline Adapter: The current router is upstairs in a home office and is connected via a telephone extension cable from the master socket. A powerline adapter is connected to this router. I'm assuming that the extension cable will be redundant and that I'll need to locate the new router downstairs where the fibre cable comes in and that I'd need to connect the existing powerline adapter to the new router. (I already have another PA for the smart TV). I think I'll need an additional powerline adapter for my laptop and printer upstairs in the home office. As you may have gathered, I don't know much about these things. Hope this makes sense.
Why not simply replace the extension telephone cable from the master socket with a Cat5e Ethernet cable from the ONT.
Thanks for that. I don't think the ethernet cable would be easier for me. I'd have to remove the old cable which is attached to the skirting board going up the stairs, around the landing and through a hole in the wall to the home office, and then replace it with the ethernet cable. What may be an easy job for you, is quite daunting for a 70 year old who hasn't done anything like that before. Also, it would mess up the paintwork.😆
Yep, an easy job for a 75 year old like me.😂😂
Do you know what model router you have? Also what model powerline adapters you have?
I take it that since the first powerline adapter is upstairs and you are wondering about a third, that the second is not near the current master socket?
The reason I ask about model numbers is that a new router is likely to support gigabit Ethernet and and WiFi 5 (or even 6). If your powerline units are not so recent when trying to buy an additional unit you may be pushed to upgrading them all which may be unnecessary.