I once asked them if we could enable IPv6 on a 1Gb DIA circuit, and the response I got back was that "we can convert the circuit to IPv6, but you'll need to give up your IPv4."
I don't think I bothered asking them again!!
(Edit "them" = Virgin Media)
Sure they didn't just mean they'd change your static IPv4 address to a different one?
Quite possibly.
But the way that they dealt with the whole thing smelt very "we don't know what we're talking about", enough to put us off.
And shifting all the IP space about would have had costs with very little return, so little business appetite to go through it.
in my case, they did this without input from me.
I only found out because I could no longer access a swath of things I used to be able to.
not virgin media, but in the EU