sanmigueelbeer" I think the home analogue phone will not be replaced. At the exchange shift will be done to logically connect the analogue "lines" to VoIP."
That's how the system has worked since system x was introduced decades ago, over BTs network not the public internet. The announcement can only mean VoIP from the premises or cabinet. A move to purely fibre requires something that looks like VoIP so they might as well just use the existing standards.
Broadband modems sometimes have phone support built in already, virgin have it disabled in their Superhub, haven't checked BT recently but they used to have some sort of support in their modems. The hardware for adapters is cheap enough that a backup battery will be most of the cost!