Niantic have announced the details for the 4th Pokémon GO Community Day which takes place on April 15th, 2018 from 2:00 PM to 5:00 PM Haiti Daylight Time. The featured Pokémon for this day is Mareep and a special move will be distributed with it but announced at a later date. The 1/4 Egg Hatch Distance and 3-Hour Lure bonuses will also be available that day.

Source: https://pokemongolive.com/events/community-day/