Hi Michael,
James looped me in and I was able to reproduce this issue. I will work with the engineering team to get this resolved.
In the meantime, you can update the trigger type to Added & Modified and add an additional filter for Due Date Is Null to create an automation that will assign a due date on ticket creation based on priority.
Trigger Type: Added & Modified
If:
Select AND to require both Filters to be true.
Priority Equal 3 (Low)
Due Date Is Null
