Certification Email Templates: Difference between "Certification Due" and "Certification Due Reminder"?

We determined in the 2 posts before yours that the “Certification Due Reminder” is sent to the Certifiers (Managers in a Manager Certification) to remind them that they have a Certification to complete and sign off on. The “Certification Due” Email Template is used to remind the Certification Owner that the certification as a whole is still open, and needs to be completed. You can see the difference in who the template is address to. These are not both addressed to ownerName.

I created another topic for this, as I am seeing the same thing. You can find it here: Certification Email Templates: Difference between “Certification” and “Certification Campaign Activated”