There are various recurring monthly in-game events for Clash of Clans, such as CWL (Clan War Leagues), Clan Games, season end and league reset. They each follow a pattern for when they occur, usually starting on a particular day each month, although the league reset has a different schedule.
Clan Games (Active Until)
The sign up period CWL usually starts on the 1st of each month at 08:00 UTC and clans can sign up to that month’s league for 2 days. Once a clan is placed in a group, there is a preparation day followed by 7 war days back to back.
Once the 2 day sign up period has ended, it is possible for Clans that aren’t participating in CWL to start classic wars.
Clan games usually run from the 22nd to 28th of each month at 08:00 UTC. They run for 6 days and rewards can be claimed for up to 7 days after they have finished.
The season follows the calendar month with the season bank loot payout occurring on the 1st of each month at 08:00 UTC.
The league reset occurs at 05:00 UTC on the last Monday of each month where all players will become unranked and players in Legends League reset to 5000 trophies. This cycle results in some leagues length lasting 4 weeks and others lasting 5 weeks.