Is it possible that Salesforce uses Labels of "Case Priority" in "Email-to-Case Settings" instead of API Name?
All email-to-case Cases have Priority API Name set to translated Case Priority Labels.
There is no way even to select these options, as they are created as "inactive".
Update: turns out it depends on launguage settings of default Case Owner. Which seems like an obvious bug, as I can't find a single mention about that anywhere.


CaseSettings, subtypeEmailToCaseRoutingAddress- see doc