UTC is the time zone based on the prime meridian, which all the others are taken as differences from. Part of the reason I decided to give all the times in UTC is that I know different countries change their clocks at different times (and in different directions) around this time of year.

UTC is 4 hrs ahead of EDT, so the 2355 UTC deadline becomes 1955 EDT. The countdown link may be an easier way to figure it all out, though.