Limit upgrade options to paid users

I have this scenario:

I have two ways to register
1. Free
2. Paid (3 plans to choose from - Youth, Adult, Family)

I want to allow the Free Registered Users to be able upgrade to any of the paid plans, but do not want to the paid users to be able to upgrade since they are on a plan already (There's no need to "upgrade" access is the same).

Essentially I do not want to have paid members see the other plans as options in the Membership Tab.

I'm not sure how to set this up. Whether i need to play around with Joomla ACL or nest plans, etc. Right now I have created 2 registered users groups (Free, Paid)

Any advice on how to achieve this?

Update: I found some amazingly flexible configuration options in the Workflow tab and this is what I have come up with. Not entirely sure this will work without more testing. What do you think?

Update: I found some amazingly flexible configuration options in the Workflow tab and this is what I have come up with. Not entirely sure this will work without more testing. What do you think?

That's the correct way to limit upgrades. Your current conditions look ok to me and will allow upgrades as long as the selected plans aren't actively subscribed.