From what i gathered, from a friend that was in Engineering management of a DNO company in Essex, that any cast iron service head with ceramic rewireable fuses (DP) should have all been replaced, by all the DNO companies in the UK, by the end of 2011 free of charge. But they didn't and still haven't achieved that instruction that came from the electrical ombudsman.
But getting back to the DNO'S charging for PME conversions, what an absolute disgrace, ...£150 for less than 20 minutes work. So what are you all paying this quarterly standing charge for then?? It was always described as a charge for maintenance and to cover system upgrade costs... Which when you think about it, should even cover the cost of a local main isolator at every service head... Most domestic installations have collected 1000's if not 10s of thousands over the years for the service companies....