Wow. Interesting. And they are not even off by seconds. It looks like the original post got "delayed" by 30 minutes -- the second poster was even able to edit twice before the original post went up. The word "delayed" is in quotes because, obviously, it was not delayed, but an artifact of a time reporting and ordering issue.
We changed our clocks Ranch Time at 2 am last night for daylight savings time. In other words there were two 1-2am's last night. Since the issue occurred during that time period, I lean towards not worrying about it unless it happens again.