Clubs rank gets re-evaluated every 30 days from the date the Club has been created. After the 30 days cycle expires, the Club points get reset, and the system evaluates your Club Rank according to the Club Points the Club earned within this cycle. If the Club does not meet that rank requirement, it would be a downgrade to the nearest rank where the Club points for club rank requirement meets.

You can find the "Status" of your Club by tapping the "Star" icon on the Club's main page.