Antarctica Standard Time is Greenwich Mean Time (GMT).
Antarctica does not operate Daylight-Saving Time
Bases and stations around Antarctica tend to keep either the time relating to their home territory or the supply line that feeds them!
Strictly speaking the South Pole operates GMT but you can walk through all 24 time zones in a few seconds!
Since 2005 this station, located at 75.06S 123.20E, is one of the 3 stations active the whole year on the Antarctic Continent (the others are South Pole and Vostok).
The station keeps GMT+8 (Perth, Australia) time zone without any daylight saving time.
In Antarctica there is also another Italian base, Mario Zucchelli Station (MZS), located in the Terranova Bay, quite near McMurdo.
MZS is active during the Antarctic summer for more than 20 years. The time zone is the same as McMurdo.
All the electric clocks are usually wrong. Something about the generators running at 60.1hertz or something makes all of the clocks run fast. So every couple of days, they have to go around and set them back 5 minutes or so.