https://twitter.com/g_pig_lover/status/771089202255650816
She may be referring to White Christmas which was a christmas special and it came after season 2 andcsome people seem to think it was season 3.
shareIMDB answers for you
http://www.imdb.com/title/tt2085059/episodes?season=3
Some of the episodes from the new season have been shown already.
San Junipero and Nosedive were shown at the Toronto international film festival in the middle of September.
San Junipero, Nosedive and Shut up & dance were shown at the London film festival in early October.
And Playtest was recently shown at the New york comic con.
I had the fortune of being able to attend the showings at the London film festival ^_^
Can't wait to watch the rest tomorrow.