Hi kbfern I have just had that exact same work done in my bungalow new kitchen loop new consumer unit, I too thought the isolation switches in the consumer unit would be sufficient.
Got a message from bp pulse saying it is in fact a separate double pole 100amp isolator switch that is required these are fitted by your energy supplier, Eon in my case.
Cost was £98.07 for the switch the top tails out of it and they supplied the two enfield blocks too.
Took about 2 weeks from order to fitting.
See pic below