Supposedly, the time stamp should indicate your particular time zone, mine never has despite the fact that I set it to ET.

Even if it did work, many people won't ever set their time stamp properly, so that is one reason.

One time all posts were synchrnized to just one time, PST.  I liked that because you could make sense of when posts went up.  Not all posts go up at the time they are written because some people are moderated.

and I'm not sure why but there doesn't seem to be anything I can do about it.

When I first started posting, my posts needed to be approved.  After posting for a bit, they go active immediately.

However, the mods can always review the post and pull them down.  If you go to your "My TER" tab and then go to the "More" tab, there is a drop down that says "My Board Posts."  You will see your history there.