G.Fast - Where does it leave BDUK funded areas?

Please accept my apologies for my ignorance, and thus asking what might be a stupid question, but...

With many parts of the UK relying on government funding to obtain "superfast" fibre broadband (25Mb+) speeds, through BDUK. I take it that we'll be back in the same position again when (or should I say if) BT do go ahead with this G.Fast that is now being mentioned? I take it this new method (which BT currently sees will offer 500Mb to "most" areas of the UK by 2025) will once again require new equipement, which will again be deemed not commercially viable for all but the most densely populated areas?

Or, is this just G.Fast just going to use the same kit that is being installed now (inckuding for the BDUK sites) just using it more efficiently?

If anyone can explain how exactly this G.Fast works and what it might entail for roll-out?

I should probably add that I doubt this "10 year" vision will indeed come to fruition in 10 years, so I'm not getting my hopes up for even the commercially viable areas just yet, let alone BDUK ones.

New kit but re-use a lot of the fibre backhaul that has been put in place, i.e. the network was built with future upgrades in mind.

Those rural areas that have shown lots of demand will have more chance of being in the commercial roll-out e.g. where they've filled more than one fibre twin for example.

ADSL launched in 2000
VDSL in 2009
G.Fast real launch rather than trials 2016 - i.e. it follows the upgrade pattern

If we were willing to wait a very good chance that commercial roll-out would have eventually got to 90%+ of premises, BDUK just made things happen quicker for some people

Investment guarantees that Virgin Media is accessing for its expansion plans may also apply to Openreach and thus mean less needed for a BDUK 3 or 4

Or the internet will prove a fad and dye out