It sounds like Auckland.
We have the same shamble over here with all the splitup between old POCO's and metering companies.
Everybody seems to be very good in providing useless numbers and you (the customer) can repeat the story over and over again.
Bureaucracys who have absolutely no clue what is going on !!
I am aware of CT sites with 5 Amp metering, which run at nearly 10 Amps and MDI pointers of the scale. doesn't get picked up in the billing by the people with no knowledge of metering parameters and maxima.
Best remedy, pull the pole fuse, service fuse yourself, get the job done, leave the existing metering on site and put that back in place when finished.
Nobody seems to care with this so called de- regulation.