Create trigger rule for variable assignee

Hi there. I am creating a simple project workflow. I am attempting to create a trigger for when a task is assigned (to anyone, not a specific person) that task will move to the “In Progress” section. I cannot seem to find a way to leave the assignee as variable and still make the rule run.

TIA

A post was merged into an existing topic: Ability to trigger a rule to assign task to anyone rather than a specific team member.