What happens to future assignments for terminated employees?

Summary:

What happens in the following scenario: A learner completes a course with reassignment rules attached. OLC generates future assignment, but the employee leaves the organisation before it is due. What happens to that particular assignment?

Content (required):

We are about to set up some assignment rules for new courses and the learners will be enrolled via a learning initiative. I'm aware that once an employee completed a course, a future assignment is generated by OLC, which is visible to administrators.

What happens to these assignments once an employee is terminated? Do they remain on the system as active assignments until an administrator removes them, or does the system automatically withdraw them?