On a normal day, I can only see perhaps seven or eight posts which go back a few days. Some days however, as today, I can see posts going back over a week which I haven't seen before. They're not posts which require me to comment on, usually ones which friends have liked or commented on.
This doesn't happen every day, and sometimes they are posts which contain information about events that I have missed because of the delay showing up on my Facebook page.
It's very strange, and I can stay on the site for ages as the pages keep coming up. Some of them I have seen before, but some others never.
Hope I've explained this clearly enough - any ideas why this happens?