Bulk Loader: Category Mapping - un-mapping and mapping the same course in one upload

Summary

Can an item be unmapped and mapped in the same bulk upload file?

Content

I have a series of courses that I unmap and map at the end of each month - this is done to facilitate reporting and an integration with a third party program.

I am wondering if it is possible to unmap a course from it's existing category and map it to a new category in the same bulk upload.  If I enter the courses to un-map first it will remove all category mappings.  Then if I enter the same courses with a new category, it should re-map them (?)