BT (UK) landlines migration to Digital Voice supporedt by Netgear?

Unless someone with an Orbi connected to a BT smarthub2 happens to notice this post, his situation sort of screams out "Talk to BT" or search for a BT user forum.

On the one hand, Voice over IP from countless suppliers has been supported on consumer routers for years.  Connect the VOIP box to the router, enter the setup information, and "talk".  IF BT is giving up on their traditional voice support and switching to a VOIP solution that they have purchased and relabeled from somebody, it should simply connect to the Orbi router.

On the other hand, ISP support for voice is tied directly to their underlying technology.  For example, as a Spectrum cable customer, everything Spectrum provides (television, voice, internet) uses specific frequencies on their cable system.  At the cable modem (or router), the frequencies used for voice are split off and used to feed the telephone jack on the modem, just as frequencies used for internet are combined into an Internet connection.  (See Data over Cable Interface Service Specification: https://en.wikipedia.org/wiki/DOCSIS#:~:text=Data%20Over%20Cable%20Service%20Interface,cable%20television%20(CATV)%20system. 

BTs smarthub2 appears to support several technologies:

Fiber to the Curb. Fiber to the Premises. g.fast https://en.wikipedia.org/wiki/G.fast  - WOW.