When does Untitled Siegfried & Roy series return?

Siegfried Fischbacher (June 13, 1939 – January 13, 2021) and Roy Horn (born Uwe Ludwig Horn; October 3, 1944 – May 8, 2020) were German-American magicians and entertainers. They were best known for their use of white lions and white tigers in their acts. Their performing career came to an end in 2003 when Horn was critically injured by a tiger during a performance.