Conditional novalidate form or element attribute by role / update

I'm going in circles and can't figure this one out. I have a specific use case where I need guest users to have the form fully validated upon creation, but I also need any one of the following (listed in priority order):

• specific roles (alternatively, authenticated user) to skip a validation for a specific field upon creation/update
• or specific roles to skip all form validation when creating and updating
• or ignoring the role, the ability to skip form validation upon updating

This one particular form field is a date field that is validated to be at least 5 days out. Customers must obey this validation. Customers cannot update the submission once they have created it.

Supervisors need to be able to enter a date less than 5 days out at least while updating, and preferably on creation too. They could skip all form validation if individual field validation isn't possible.

If involving roles is too complex, we could simply skip the form validation upon updating, but it would still need to be in place for creation.

Does anyone have any suggestions for the best way to achieve this?