Openreach plan to switch off the public switched telephone network (PSTN) in December 2025 and move everyone to an IP based connection.
Traditionally of you required a telephone line, Openreach would supply it to your premises as a fully working product, complete with telephone number, dial tone, caller ID etc. Then, if you required a broadband connection, this was then ADDED to the telephone line.
The modern approach is to turn this scenario on its head and ADD the telephone service TO the broadband connection.
From December 2023, 2 years before the closure of the PSTN service, Openreach will only supply an IP service via FTTP or SOGEA. If the service is via FTTP, then you will have a fibre cable from the network directly to your premises. If your service is SOGEA, then you will still have a copper pair to your premises delivering the broadband, but crucially no telephone service.
The telephone service will still be possible and you can port your existing number, but this will be via the internet and be provided by Communications Providers (CP's) like Sky, TalkTalk & BT etc. The new routers will have a dedicated socket for you to connect your telephone equipment.