Presumably then you are currently on PSTN telephony ( phone in wall socket but not working ) , because of your imminent migration to DV you have been sent a SH2 which you have connected, it shows that DV hasn’t yet been configured, so the PSTN wall socket should still be working ( but isn’t ) .
Obviously I’ve no idea what you have reported, but it should have been that your phone ‘line’ wasn’t working ( NDT , no dialtone ) but your broadband is fine , and reported as a phone problem not a broadband problem, if that was done , it’s possible the migration to DV has been assumed to be the issue when it’s probably the PSTN exchange equipment that’s faulty ( one of the reasons for moving to DV is the PSTN exchange equipment is now very old and prone to failure ) .
A ‘BT’ engineer is actually the correct ‘department’ in that Openreach are not responsible for PSTN equipment ( the actual switch in the exchange building ) but the home visit by BT seems bizarre, nothing can be fixed by BT in your home if you are still PSTN , an exchange engineer visiting a house is nonsensical, suggesting although BT , they were not a PSTN switch engineer .
The appropriate response to NDT reports, is Openreach check from the customer to exchange and if the exchange at fault , ( your individual line circuit ) it is not repaired , you are transferred to spare , adjacent ( but working ) line circuit by Openreach , ( who call BT , get BT to reconfigure your appearance in the exchange equipment to a new line circuit location and Openreach ‘rejumper’ your line to that new circuit )
Given the fact that it’s now less than two days to the DV changeover , it’s probably pointless attempting to get this resolved now , simply wait until 24/20/24, chances are DV will work and the faulty PSTN is never going to be reissued to anyone , obviously you move your phone instrument to the router from wall socket , once done , ( and working on DV ) ask BT about compensation.
