They sometimes simply can't give an answer and no one from the DNO is going to come out and remove the cut out fuse so you can see if it's 60,80 or 100 amp.One you ask the customer to obtain he information.
Two you obtain the information and charge the customer for doing such.
I do understand they are required to give you the info tho but it's not always the case.
Maybe it a north east problem?