AgentType priest vs heretic

[alpaca]

The problem could be that the traits aren't cleaned by game hardcode when the character turns heretic, and that the NaturalPriestSkill is only available to priest characters, so you probably couldn't lower it again.
Changing the trigger would have no effect on this behaviour if that theory is true.

A possible workaround would be to make the trait available for all characters and differentiate in triggers, in which case your cleaning trigger should start functioning.

[FactionHeir]

Some priest traits were actually cleaned when a priest turns heretic by default in the character_trait file, but I merely expanded on the number of traits cleaned (as it wouldn't make much sense to have say a bishop heretic or a guildmember heretic) including naturalpriestskill, which somehow seems to be the only trait having a problem thus far (and its the only trait given on creation of any priest agent type)

[FactionHeir]

After extensive testing, setting NaturalPriestSkill to priest and heretic and giving out the trait to priests but not heretics solved the issue.

[alpaca]

After extensive testing, setting NaturalPriestSkill to priest and heretic and giving out the trait to priests but not heretics solved the issue.

You still have your cleaning trigger in, though, don't you?
Or does it work out of the box?

[FactionHeir]

I got my cleaning trigger still in, yes.
CA only cleaned 2 traits from priests turning heretic and they even had the same trigger name, which would cause some issues. I have triggers to clean every trait except BadDenouncer, Dogmatic, OpenMinded and SecretlyFemale.