I used to live in OX10 and the DNO was SSE. I did a CU change for my sister in OX3 last year and that is also covered by SSE.
In my sisters house the tails were only 16mm so I called SSE on their emergency line, telling them their installation was unsafe. They were there within an hour on a Sunday, and replaced the tails without questioning it.
Sometime it pays, rather than quietly request they do some work, don't pus sy foot around, just phone the emergency line and report a dangerous condition. By the time the bloke is there, he's quite likely to just do the work.
The "fun" comes when the customer has changed electricity supplier. Then the DNO won't come out, insisting instead you contact their energy supplier. I had this once with an N power customer again 16mm tails that I thought needed updating. DNO (SSE but this time in Scotland) didn't want to know and N Power were hopeless. I virtually screamed at the woman that the installation was unsafe, but all she could say is put my concern in writing and they would consider it. I did that but never did follow it up to see if they changed the tails. A good reason for keeping your DNO as your electricity supplier if you ask me.
