Hi @josh_oman,

The best practice for controlling access to fields/data is via ACL's (Access Control Lists). 

You'll need to elevate your role as an admin and edit/create (depending on the current ACL's already implemented) an ACL for both the urgency and impact fields (Seeing as they control the overall priority - again assuming you've maintained the OOB configuration).

With regards to your filter, it should be as simple as checking whether the major incident state is either Accepted or Proposed vs being empty (or any other state).

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Thanks, Robbie