I've done that but how do you put on a new container?
Simple if your crownboards have two porter escape holes. Gently slide container along until new one (following) is over the hole. Slide the old one over the other escape hole and leave them to it for a few minutes.
I use the deeper plastic 'chinese take-away' containers because they are transparent, hold about a kilo of fondant at a time The fondant does not dry out in storage because the it is covered initially with clingfilm, then the lid. When used the clingfilm is slashed for access by the bees. The bees do not chew it as it is laying on the crownboard, it is not propolised down and any bees inside are not squashed as the container is moved(they are walking on the clingfilm). If you wanted to, I suppose one could easily slide a card under and leave it by the entrance if the weather was warm enough. Your imagination just needs using to accommodate your particular situation. There are other ways of clearing the container, if you were really bothered about it!
RAB