Cheers folks, Al's advice follows my feelings! The good thing is that with the neighbour's garage out of action we have been able to dig the trench and lay the new cable. The ballast and concrete to fill it is due 3 hours and 40 minutes ago.....(!).......but when/if it does arrive and we get the trench filled and full power restored to all circuits, then at least we will have good certificated electrics. Several buildings in the yard were badly damaged by Heinkel Kabines, er 111s, during the Vera Lynn War, and I think the awful electrics were botched together then to get the buildings operational again quickly.
We have been wanting to renew the power cable since we have been here because it was stretched and sagging, and because we were supplying electricity at our cost to other buildings and businesses in the yard. Totally illegal, but whereas pre-privatisation the LEB would have been legally obliged to renew, we bought the building post-thatcherisation, and now the power company's only legal obligation is to make as much money as possible and leave all infrastructure to rot in hell, same with railways, water, and gas. Interesting to note that if we do anything to "their" cable we commit an offence, but if we ask them to replace it, then it is "ours".
Another reason why I have a deep distrust of Men In Suits Who Are Not Called Bob Purton, and that also applies to Women In Suits. I have had various dealings with developers, lawyers, Assessors, Councillors, Bankers etc., and my opinion of them all is "not great".