In article ,
"Andy Pandy" writes:
How easy/expensive is it to get the supply & meter upgraded to 100A?

It used to be free, when your supplier owned the network.
I haven't needed to get it done since the businesses were
split up. No one seems to worry about 40A meters -- they
are commonly used on 100A supplies.

Your own CU and wiring had to be already suitable for 100A,
main earthing up to spec, etc. or I suspect they would
refuse the upgrade.

--
Andrew Gabriel