Department Hierarchy and Department Changes reporting

Content

I have been working on rolling out a department hierarchy for my company. The hierarchy is complete and working but i am looking at how it interacts with things like:

Department name updates

Departments being end dated

In both cases I would like to be able to report historically. 

Example: Department name update: If name changes on April 1st 2021 then prior to that date it would show old name

Example: Department end dated April 21st 2021. Reporting on departments prior to that date would show it.

To this point I have been unable to get this to work. I tried headcount and FTE and am not sure what I am doing wrong here. Any suggestions? I am trying to do this all within OTBI is possible