Complex sentence: Season 9 ended with Mo Collins and Josh Meyers leaving the cast to pursue movie careers, so last year's featured cast members-Daniele Gaither, Keegan-Michael Key, Nicole Parker, and Jordan Peele-were upgraded to repertory players.
Split into simpler sentences: Season 9 ended with Mo Collins and Josh Meyers leaving the cast to pursue movie careers. That meant last year's featured cast members-Daniele Gaither, Keegan-Michael Key, Nicole Parker, and Jordan Peele-would be upgraded to repertory players.