I usually have my games sorted by "time of last move", descending so that the games most recently played come first. This way I can progress on my games while my opponents are online, making the games faster (and easier to keep them on my mind too).

Whenever a game shows up and I think that I need some more time to think about it, I click the PlayLater button and it doesn't show up again. If in the process I go back to the main page, it's natural the games I decided to play later will come back again.
However, I've noticed that if I take too long playing through my games (usually, when I'm playing from work where I play a couple of games at a time and then go back to work) I noticed that, after some time, the "PlayLater" games come back up again, even if I have some more games that still haven't showed up.

So, what exactly does this button do? Does it just put the games on hold for a while? How long is that while? Could it be configurable? Or is this some sort of bug?