How do get the same results as changing Level Load Rule on an Academic Program over time?

I am looking for some information on updating the Level Load rule used on an Academic Program. Specifically:

What is the reason that a Program cannot be updated to allow the Level Load Rule to be updated on a new effective dated row?

If the Program genuinely needs a new Level Load Rule, what are our options? Creating a new Academic Program for each situation (and giving it a new Level Load Rule) would mean enormous an enormous amount of work and change for our clients. Would using Correct History to change the Level Load Rule on all effective dated rows of the Academic Program table for a specific Program be an acceptable solution? Or would the answer to my first question explain why this would be a bad idea?