How/Why is my specialization number of activities changing?

Summary:

We noticed yesterday that a specialization that has 25 activities was only showing as 14 required. This was extremely alarming, no one has edited the sections. I decided to take a look back at completions for the last year and am very concerned. The number frequently changes but again, we're not making edits to the specialization. You can see in just a snip of this one day, that the number was different for employees ranging from 17 to the correct 25. What is happening?!

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