Following Governor Baker’s announcement prohibiting all gatherings of 250 or more people, Chevalier Theatre has postponed A Bowie Celebration, a new concert for 2020 in which key alumni musicians of David Bowie’s bands from across the decades play two of the greatest albums of all time — Diamond Dogs and Ziggy Stardust — in their entirety. The concert has been rescheduled for Friday, September 11, at 8 p.m.