As a user, I would like 'thank you' emails not to affect original resolution date of the ticket. Now if I resolve ticket within due date it still can be reported as completed-overdue if client's 'thank you' email reopens the ticket after due date. It should not affect the user KPIs.
Enate decided to build an integration with Re:infer (https://www.reinfer.io/initiatives/auto-triage) to delete this email and not open the case/ticket for these types of emails.