Status as Read Only

Summary

How to make incident status read only after a certain amount of time has passed once it has been solved

Content

Hi, does anyone know if there is a way to make an incident status as read only after a given amount of time once an incident has been solved? Unfortunately in the workplace rules it only allows you to choose based on a calendar date and not a range of time. I have also attempted this through a business rule, but come across the same issue. We are not wanting to allow anyone be able to unresolve an incident after a years time.