It’s not you. It seems to be the way the software is set up. The programmers didn’t think it was important – kind of like the lazy coders who don’t notice when it not only says 0 seconds, 2 seconds, 3 seconds, etc. But also 1 seconds. When I was writing up a database, I made sure that it was as grammatically correct as possible (just a simple IF, THEN).
I’m not an author or anything, but I’ve seen a few instances of two chapters being posted within a few minutes of each other. I don’t think they’d let you post 3 or 4 chapters on the same day though. I know one author who was posting chapters daily. And the automatic postdating of chapters seems to be working again.