That's funny. I think all cats are the same. For hours they don't go near the litterbox, but boy the minute you go to clean them, one or more are right there waiting with legs crossed.
So you have to rush while saying, "Okay, okay, hang on, i'll be finished in a minute."
The second it's cleaned, fresh litter put in, whammo, you're scooping it out again.
I swear they do this on purpose. LOL