Odd duck. I have not changed that logic.
I did run a test on my site and it seems that something changed in how time is processed on the server.
If you go to the Debug Tab for the TopBar with time settings, you'll see the time info for the server and for the TopBar. Here is an extract from my test site:
Server Timezone: UTC
Current Time: 01/06/2014 17:40 (UTC)
TopBar Time Check:
Starting Time: 01/06/2014 18:00 (UTC) - As entered: 01/06/2014 18:00
You'll see the server time is UTC. To make the TopBar time settings work (for now), you'll need to enter the Time on the Control Tab as UTC.
Let me know if entering the time as if you were in the UTC timezone works for you.
I'll need to work on what changed and how to revert the plugin to use the local time for data entry.