2011

From Terminator Wiki

2011 is the year that Judgment Day was said to occur by the terminator Cameron Phillips, who was sent back in time by John Connor in the year 2027. This Judgment Day took in an alternate timeline to the Judgment Day shown in Terminator 3: Rise of the Machines (2004).

According to Cameron, Skynet was activated on April 19th and Judgment Day occurred on April 21, 2011.