Welcome to DST, those of us who changed over this morning at 2 AM. The automatic detect of the time change does not seem to be working with the new rules.

To change your post time, go to your control profile (User CP in purple box at upper left) and select "Change Options". Scroll down and you will find a box that says something like "(GMT -6:00) Eastern Time" or whatever is appropriate to your time zone. Choose the one that is one hour less and remember to click "Save Changes" before you exit. I chose GMT - 5:00 and am now correct.

Note: Below the time listing, is a DST correction box. I've set mine to OFF just in case it decides to change my time again in April as it used to do.

Check your time before you change it though because most people will not be affected by this. If you have auto-detect selected and have javascript enabled, and your computer time is correct, then it should all work together to update automatically for you. If not, Ruth's advice will get you there

Yes, definitely check your time by making a test post. I had auto detect selected and Java script enabled and it didn't change for me. My computer time changed automsatically but not the posting time on the websites I visit.