Hi there in terms of the 3 hour rule, I think you're right, if there is a fine they will do anything to enforce.
I know often, I'm from Bolton, that cars that are not ev seem to be taking up spaces, or cars being on all day so no room for others to use.
It's really annoying that people with no ev still continue to park in those spaces.
We don't have any 3 hour rules (yet) I'm sure we will do in the future.
I have just managed to get an EV charger fitted, I know we are very lucky. I'm a bit concerned because my electricity bill has gone up and they have removed the cheaper night tariff too. So I'll have to keep an eye on it and charge at work where its free!!