Functionality Changes Around Course Instance Expiration Date?

Is there any functionality change associated with the course instance expiration date? I am hoping the expiration date can be used to "lock down" a course at a certain point in time. It would great if learners were no longer able to complete unfinished models after the deadline or in some way have the system indicate that it was completed past the deadline.

If course instances are not able to accomplish this is there another way to use the system to do this?

Thanks,

Ash