BT have said they will be launching wires only FTTC next year. It will be a bit cheaper than the engineer install, and means end users getting their own VDSL modem. On face value, this seems good.
However, this is going to be a problem in many ways. The big issue with ADSL is that it includes all of the grey areas of modem to modem communications over a copper pair. This means you cannot tell if a problem is the modem at the exchange, the copper pair in BT, the wiring in the home, or the modem at the customer premises. So BT can, and do, blame the end user modem as the cause of many problems. It means we have to replace the modem before we can really start shouting at BT to fix things, and even then they will still blame the customer equipment. It is the reason SFI charges were invented in the first place - charges that are more than many years profit on a typical ADSL line and take a lot of time to dispute every month.
With FTTC and the engineer install BT are providing an Ethernet service. I.e. it is a service at the Ethernet port on the BT VDSL modem. They can test up to and including the modem and even confirm if the modem can see the Ethernet port up or not.
It means any line issue, whether modem at either end or copper pair is always BT's responsibility to fix. FTTC faults are almost always "clear cut", BT see the same issue and get it fixed, and do not blame customer equipment or make a charge.
With wires only we open the whole can of worms that is SFI charges and blaming the customer equipment. It also does not fit with the underlying service being an Ethernet service. It is all very messy.
We have considered not offering this cheaper wires only install, largely because the saving will not be enough to cover buying a new VDSL modem, but also because of the fact that BT would no longer be responsible for the modem.
However, we can see a whole raft of issues. We'll need to keep careful records of which lines are engineer install and which are not. And, sadly, we have to do this even if we only offer engineer install as someone could migrate an FTTC service to us that was not engineer install. We have no idea if the checker or tools to BT will tell is whether it is or is not engineer install, and we obviously need to know when reporting faults.
We then have the issues with engineer installs where the end user happens to have changed the modem to one of their own. We have to know, and have to ask the end user to put the BT modem back for testing.
It is going to be a nightmare.