There is a problem with the disconnect message box and having "Show connect/disconnect" turned on.
If this option is on, the disconnect message is outputted to the world after the disconnect message box ends. This shows an incorrect time in the disconnection message, and can actually be completely inaccurate, especially if you have Auto-reconnect on (ie. it will show Disconnected, but you will actually BE connected).
So basically, if you delay in clicking on the disconnection msgbox, it will not work as intended. The "show disconnect" part needs to be outputted before the msgbox is called.
The dates and times for posts above are shown in Universal Co-ordinated Time (UTC).
To show them in your local time you can join the forum, and then set the 'time correction' field in your profile to the number of hours difference between your location and UTC time.