The MiL was migrated to "Home Phone Standard" (according to BT account on their website) yesterday. Everything done at the exchange. The account on the BT website is a bit of a mess but that's another story.
Things to note/check:
1) Check CLI is being received for incoming calls. Sometimes it doesn't
2) When dialling, prefix local numbers with the area code
3) BT DV comes with voicemail essential. This cannot be disabled through the website. Suggest increasing to the longest duration possible, and this would allow a local answerphone to kick in and/or the MiL to move to the phone to answer it.
aquiss FTTP 80/20 and A&A VOIP