Lock Request Limits for in progress tasks so the client can't change it depending on their service subscription.

I have 3 subscription tiers, each allowing a limit of “active tasks”. I want to let the client add as many tasks as needed to the queue which is fine, but limit the amount of tasks allowed in the “in progress” section depending on what plan they are subscribed to (1, 5, unlimited in my case). I could create a board template for each scenario, but I want to lock the ability to change request limits on the client side.