Course content mysteriously downgraded from version 17 to 16 after Olive upgrade

A couple of months ago I upgraded a client’s site from Maple running on Kubernetes to Nutmeg running on a newly created Kubernetes cluster. I performed these data upgrade steps on a standalone Ubuntu instance running tutor local, which resulted in the course content correctly and successfully being upgraded from version 11 to version 17 (see the left-hand screen shot). A couple months later, sometime after having allowed tutor to automatically upgrade the new deployment from Nutmeg to Olive, around half of the courses have downgraded themselves to version 16.

How did that happen? And more importantly, how to I upgrade version 16 course content back to version 17?