Hum ok,
I dont want to add or remove members from the rule based group
I want to run a script against any added or removed users from this rule base group.
So any new added user should get a specific extensionAttribute6 and any removed user should get this cleared.
I tried now this scheduled task
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And changed my business rule to the new temp group.
For now it seems to work, I have my group based on rules and criterias and my users attributes are updated correctly.