My girlfriend's birthday was about two weeks ago (August 15th). This morning, on my newsfeed, a girl friend who isn't really a girlfriend of hers (long story) says "Happy Birthday Ms JuniorNB". It's a direct wall post to my girlfriend's wall. Weird thing is, it says the date of the post was August 15th. But next to the date is a little clock symbol and when you hover over it, it says "Added on Thursday, August 27th at 10:13 am". It also appeared on her wall when it was originally posted on the 15h. So what exactly happened today at 10:13 that made that old post reappear on her wall and on my(and I assume everyone else's) newsfeed?