I usually go through Advance Screenings or gofobo, these are the Advanced Screenings scheduled right now for 21 Bridges, but I would guess more will be coming:
https://advancescreenings.com/movie/21_bridges
California
Daly City 11/20(wed)
San Diego 11/20(wed)
Sacramento 11/20(wed)
Connecticut
Hartford 11/20(wed)
Kansas
Shawnee Mission 11/20(wed)
Massachusetts
Boston 11/19(tue)
Michigan
Troy 11/20(wed)