MrBadger
Badger out
My concern is that potentially, all my Electrical certificates are wrong now. which in THEORY might lead into some issues if I sell the house, as documents supplemented will not be correct.
Electrical certificates are not retrospective. If they were correct at time of issue then they remain valid.
If however you had further work undertaken, then the new certificates would then be based on the new fuse size.
Likewise any new diversity calculations would be based on new fuse size but also the revised calculation which sounds like it would give a similar result.