Hi @bernard_hamill,
In beta (not production), I just quickly tried a bunch of different copy/import options from a course with multiple sections to another course with multiple sections. Before the import/copy, I configured an assignment to have different dates for the different sections. When I copied/imported, none of the dates were copied.
I believe this is because the only dates (when desired) that are copied/imported are "Everyone" (or "Everyone else") dates and not dates for individual sections (or students)
This is probably because from a behind-the-scenes perspective, it is too difficult to align the sections in course A with the sections in course B. Another reason, related to that, is because course A could have 3 sections and course B could have 4 sections and the copy/import process would not know how to align them.
-Doug