Trigger for "Auto Email to New Employee"

Summary

Which employee status change triggers the "Auto Email to New Employee"

Content

It was my understanding that when an employee is moved to "Onboarding" status, this is the trigger to send the "Auto Email to New Employee". In error, some employees were moved from Terminated to Employed and they received the auto email. Can someone please confirm which status triggers the auto email and whether we have control of this or can see this somewhere in our system?