Your timezone should be -5 (Eastern), set auto clock to ON. Set your local time. Then, either wait 24 hours or reset your system. It will go out to the NTP servers on boot or once a day and get the accurate GMT time then apply your offset. Data in your log files for graphing will be messed up until the times work their way through. If you want to remove your log files so you start clean, there's detailed instructions in the User Guide.