My experience of similar (possibly not identical, but it involved overhead lines, trees, booking tree surgeons, cherry-pickers and such).
A mobile network thingy will likely be shipped out to the affected person. That will work (of sorts). Use it to test mobile network connectivity/speeds within the household. It could provide insights. It could make the mobile connectivity 'maps' (as provided to Ofcom by providers) into a bit of a possible fiction. In less urban areas (where mobile reception can be 'patchy') this is possibly important.
Then BT will send a letter asking for banking details, because they want to charge you for using the EE device that was sent to you (to temporarily provide connectivity whilst the landlne was down, because the outage was for an extended period).
The documentation/instructions provided with that EE (?) device regarding its return may mention that you'll be informed when to return it. Don't expect such. It my take two or three phone calls to Plusnet to get an answer.
This all suggests there's a lack of process and procedures within the BT group. IMO.
I could be wrong, though.
