As customers you should check that your fuse board can be turned off and that breakers can be turned off.. i say this as recently i had a customer who had a board that had all but failed, and the result was a board that could not be isolated by any other means than pulling the fuse from the service head! (Some thing that ideally should never be done by anyone but the DNO)
Now in this case the board had become dangerous and started smoking so it had to be dealt with in a priority way. But this brings me to the other recent development.. there is currently serious supply issues with getting alot of parts in a timely fashion and this poses its own problems if your on a priority job.
The moto is please check you can turn your breakers off even if just once a year.. test your RCD test buttons every 6- 12 months.. its better to check than be left in the dark or with an unexpected bill at maybe a time that hurts more than others.