Hi ignomony
Firstly, apologies if my comments are a bit sketchy but my knowledge of these matters is limited.
It sounds like E.ON are the electricity distributor for your area and, as such, responsible for this type of disconnection/re-connection.
I have done some digging and these disconnections tend to be where a property is undergoing renovation or in a state of disrepair. We may have been contacted by the owners, past or present, and advised this work was going ahead. Alternatively, a concerned neighbour or member of the public may have contacted us if they thought there was a danger present.
In these circumstances an engineer would have carried out a survey and if they thought a safety issue was involved would have recommended disconnection.
Not knowing the full circumstances of your property I can only speculate but if the above was the case E.ON would have a duty of care to make the supply safe.
This type of job would be considered a Service Alteration and re-connection is chargeable.
As I say, I am only speculating and would advise you to contact our Business Energy Connections team for specific advice about your circumstances.
Again, sorry for the vagueness but I hope this helps a little.
Malc