Special:Badtitle/NS2001:Contact the Moderators/@comment-27729796-20180112041553/@comment-5050406-20180112053638

Besides birthdays, the only in-universe dates with solid evidence I can think of are that After School Lesson happened on April 1 according to the Japanese title card and Makoto Naegi visited a forum about Hope's Peak Academy on August 20, 2010.