Rules:
Clan movement/ representation
Every player must be in the clan they represent on the start date of CL 12.
If a player played for Clan X in CL 9 and moved to clan Y in CL 10, then they can not represent Clan X in CL 11. This rule is meant to stop free movement of players and restrict the advantages gained via allied clans (For ex - FakeNamePlayer for Masters/Apex, Lynx/101st, Masters/Apprentice, GG/GGr etc). The only exception to this rule is if Clan X drops out of the Clan League.
Note : This rule was tweaked from CL 10 rules. The extra waiting time was reduced from 2 to 1 CL.
Obviously it should state, if Clan Y drops out of the CL, as the current wording does not make any sense since you can't play for a clan, which drops out of CL.