Michael Chare wrote
Rod Speed wrote

And our VDSL2 service doesn't even allow a landline at all, basically
because doing it that way gets better modem synch rates.

Who supplies that service AAISP?

NBNco. This is in Australia.

No phone calls in a power cut then!

The nodes, what you lot call the cabinet, does have a
backup battery in it and fiber optic back to the rest of
the network so if you have your router on a UPS you
can still make phone calls until the UPS runs out.

Almost everyone has a mobile and our mobile bases
all have battery backup so in practice most use that
if they need to make a call during a power cut.

While I do have two voip services over my vdsl2 service,
I dont ever use them. I make and receive all calls on my
mobile now because the mobile works much better than
the two panasonic cordless phones I have on the voip
services and its more convenient to have all the contacts
and past calls on the one device. And that obviously works
just as well when out of the house too. And its much cheaper
at $10 per month for calls and texts to any landline or mobile
in the country and 1GB of data which is plenty in the car etc.