midnight on the day they were assigned. This of course was before the day of uploading and submitting them on something like Blackboard or Canvas. However, he said that if they were delivered to his house, his kids may be upset if there weren't any treats brought with the assignment.
Basically what that meant was that the night a big assignment was due he would get about half the class showing up at his house dropping off their paper along with a bag of candy.
I had an English teacher in college who had "due dates" attached to all our assignments, however also told us that as long as everything was turned in by the last day of class we would get full credit on all assignments. That being said, the nature of the class would have made it impossibly hard to complete all the assignments at the last minute so things were generally turned in on time (or within a week of their due date), but it was nice having flexibility, I guess.