The next Pokemon Go Community Day will take place on January 19, 2019 and will feature the Penguin Pokemon Piplup! The event will also feature three-hour lures and 1/4 distance incubators. The exclusive move is yet to be announced.
The event will take place on the Northern hemisphere from 11:00 am to 2:00 pm, and on the Southern hemisphere from 3:00 pm to 6:00 pm, based on your local time. You still have an extra hour to evolve Piplup or Prinplup into Empoleon and get the exclusive move.