When does Citadel return?

Citadel is an American spy action television series created by Josh Appelbaum, Bryan Oh, and David Weil for Amazon Prime Video. It stars Richard Madden and Priyanka Chopra as Citadel agents Mason Kane and Nadia Sinh. The six-episode first season ranks as one of the most expensive television series ever made. Multiple non-English language spin-off shows have been announced, with settings in the Italian Alps, India, Spain and Mexico.
The show is described as an "action-packed spy series with a compelling emotional center" It includes spinoffs set in the Italian Alps, India, Spain and Mexico.