The emergency services once knew my (different) address, I thought the DNO might have access to the same information. Maybe I should ask the DNO where they got the information from.
... nested quotes trimmed ...I would never have told any energy supplier the proper landline number. I might tell them the VOIP number. All calls are made using VOIP
Someone has, as that’s how the DNO’s get hold of peoples phone and email addresses. They have no other way (unless of course you’ve made contact with the DNO before).
Even the emergency services don't have a fully joined up database (and they are certainly not sharing this with DNO's for the purpose of sending out service comms). The emergency services (if by this you mean the 999 control room) are able to see where a number is registered to as they do have access to this information via various suppliers. Usually the details they have for individual people (thus knowing where they live) comes from previous calls to 999 (from anyone who might have named you) and from the various databases held by the police.
The police databases are not linked for example to council records, so even then the police can often have no real idea where a person lives and thus can often have addresses you have lived at many many years ago popping up when speaking with the control room (or reporting an incident directly with them).
We don't even have a fully joined up warning system as yet when it comes to war, so although there are many many databases capturing our data, they are not being used in the main to benefit us