I'm sorry to hear that you have to talk to BT's IP migration team, I did too until it became obvious that most of them had no clue what was happening (they came to us - an NHS body - with essentially an "it's all going to be awesome, bear with us" holding message about 18 months ago...
Gave them a chance to prove just how awesome and seamless with a small health centre. They failed BIG (lost the main incoming number and the DDI range for 48 hours - blaming their records, the same records they're billing us on).
The replacement product was more expensive than the ISDN30 it was replacing given the call packages available didn't include "free" mobile talktime like the ISDN package did). We've voted with our (your) cash - we're going elsewhere (that trial was the exact opposite of the BT one - smooth as silk, more features, cheaper, support where you don't have to tell the same take 352 times,...)
Doesn't detract - for those home users who solely have a plain ol' phone line (Those with Redcare etc do not fit that demographic) - they will essentially get a low bandwidth DSL line (DSL has to be copper) with an ATA port (unless the place has been fibred up - but entering every building to install fibre is going to be a task and a half - no way is that going to happen in 3 years - the fibre won't be in the street for all by then anyway by Openreach's own plans)
Retiring the copper is absolutely not a prerequisite for retiring the legacy TDM phone system as much as BT's IP migration team might wish it. If they're parroting that they are very much mistaken and need to read Openreach's documents more closely.
Also, remember we've been here before - 21CN was supposed to do this 10-15 years ago - an idea what seems to have been taken out the back and quietly shot (or resurrected as this project).
I personally have had doubts (for the last decade at least) that BT Retail even want to be a telephone provider - they seem like they're far too interested in being a TV provider.
