Check it out via the link below.
Treyarch posted about updates to Call of Duty: Black Ops 4 including info about the holiday events, a new limited-time mode in Blackout, 2X XP, etc. Take a look at the link below for details.
https://www.reddit.com/r/Blackops4/comments/a5y8ta/dec_13_update_holiday_event_in_blackout_winter/