You are conflating two things , Digital Voice doesn’t need an engineer visit ( you don’t need an engineer visit to remove your phone cord from the wall socket and plug it into the router socket ) but FTTP does need an engineer visit for the initial installation, your post stated you were getting an engineer visit for DV ( not true ) you then quote the communication that clearly states
1. "..we'll be in touch to arrange for an engineer to install Full Fibre at your property"
DV and FTTP are not the same thing , DV doesn’t need FTTP , initially you didn’t mention FTTP .
Is this conversion to FTTP effectively out of the blue ( no contact to renew your contract or take ( or remove) other services ? or it a consequence of you contacting BT , or BT contacting you , and whatever was agreed regarding service , came with a migration to FTTP ?
Generally speaking , no one is just contacted by BT or Openreach ’ out of the blue ‘ and told ‘we have decided, without your consent or agreement , to change you to FTTP ‘ .
Depending on what’s required, an Openreach FTTP installation will be no slower than Alt Nets , obviously you don’t know the lead time between this Alt Net taking an order and completing it , and although it may seem attractive to order on Tuesday and be installed on Wednesday ( as an example ) it doesn’t bode well for the long term sustainability of that Alt Net if they are so under occupied with work they can install so quickly, as a ( admittedly poor ) analogy, if you needed a plumber and rang around , the decent ones ( that get work from recommended and repeat business ) are not likely to be available immediately, the cowboy on the other hand that doesn’t get recommended or repeat business will be ‘around in five minutes’ .
