What Personalization Bindings Exist on the Request a Position Change/New Position forms?

Summary

Make read-only personalization changes to the Request a New Position form without altering the Request a Position Change form

Content

Has anyone had any luck making a field read-only on the Request a New Position form without also altering the Request a Position Change form (or vice-versa) through personalizations? I assume that we can bind onto the user roles that the user has (make it read only for Line Manager but enterable for HR) but are there others? I know that in 19B some new pages allowed the action/action reason to be utilized but it doesn't look these work on the position pages. Has anyone tried any other binding rules with success?