Christchurch is the logistics hub and support base for the US presence in Antarctica, so I believe all US facilities on the continent conduct their work in that time zone.
Well, not Palmer, since that's supported by a research vessel from Chile.
It's also amusing because the tourist camp less than a km from Amundsen-Scott also goes by Chilean time. The tourist camp staff invited us over for Christmas when I was down at Pole, but it was like 3 am for them...
'The station uses New Zealand time (UTC+12 during standard time and UTC+13 during daylight saving time) since all flights to McMurdo station depart from Christchurch and, therefore, all official travel from the pole goes through New Zealand.'
It's also amusing because the tourist camp less than a km from Amundsen-Scott also goes by Chilean time. The tourist camp staff invited us over for Christmas when I was down at Pole, but it was like 3 am for them...