Can I cross-list or de-cross-list sections after a semester has already started?
As a best practice, you should plan to not cross-list or de-cross-list a course after a new semester has started. If students have already submitted assignments, and you cross-list sections for that course, student submissions and scores will be lost for the section which is being moved. However, if you are willing to accept the consequence for potential lost submissions, sections may be cross-listed at anytime.
Faculty have the ability to cross-list sections by themselves. However, to de-cross-list sections you must call the FTC and ask for someone with Admin rights to de-cross-list sections.