When creating new courses for the next term, our institution usually copy+pastes due dates for each assignment from an excel sheet that tracks the new dates. 

I've recently learned that Canvas has a setting that should simplify this. However, when following the steps in this post for shifting dates during course copy, it looks like there are no due dates transferring from the previous course at all. The "Edit Assignment Dates" feature is completely empty. I've also tried importing the content again, and still nothing.

Is this a bug? Am I possibly missing a setting? Any help is appreciated!