When my school switched to Canvas, one of my favorite things was that I could set a soft deadline and a hard deadline for each assignment. (In our previous LMS, you could have the soft/hard deadline for some assignments, but not for quizzes, and quizzes are the only kind of assignments I use, a.k.a. Gradebook Declarations.)
So, for every assignment in my class, I set a due date in Canvas, and that is the date that shows up in the Canvas Calendar. These due dates are at midnight. So, for example, if an assignment is due on Tuesday, I set the due date at Tuesday midnight.
Then, I set the available-until date until noon the next day, which gives the students what I call a "grace period," a kind of no-questions-asked extension. So, for example, that assignment due on Tuesday at midnight continues to be available until noon on Wednesday.
When Canvas launched the new Gradebook, I ran into serious problems with my system: Canvas started putting red "late" labels on the work my students turned in during the grace period. What a mess! Here the students were doing exactly what I told them to do, using the grace period as needed to complete their work (good!), but Canvas was putting a punitive red label on their work (bad!). Luckily for me, James Jones wrote a script that I can run every week to remove all those wrong labels; you can see how that works here: Remove Gradebook Labels.
