There is a place in your (our) personal folder for this site (User CP in the grey line above) where you should set the time for the time zone that you live in and/or want to show up on your posts. Go to USER CP, then down the left side to EDIT OPTIONS, when that comes up scroll towards the bottom and there will be a drop-down menu to select your time zone.

Some people may have not set their time zone correctly or may have never set it at all, thus you see some out of sinc times when they posts.

Grumpy