BruinLearn assignment unexpected hiding
Solution
Yes, Available Until date.
One way to set is Assignment => Three dots => Edit Assignment Dates, then can see them all in the same place.
In the alternative, Multi-Tool => Due Date Modifier
Multi-Tool is loaded via Settings => Nav, move from the Bottom, Up, or Three dot => Enable.
Problem
In regards to the quiz grades changing, essentially what would happen is that a group of students would complete the quiz and their grade was automatically hidden. After a few days, one of the teaching team would post the grades so all the grades would be visible. Once that happened, some students would realize that they forgot to complete the quiz, and then would attempt the quiz. When the late students did that, the new grade would automatically rehide the grades, which meant the teaching team had to repost grades.
While I cannot make that happen again on my end, I think one way to stop this from happening is to set both a due date AND an "available until" date; the latter will lock the quiz preventing students from completing it after grades are posted. Attached is a screenshot showing what it looks like. Professors will have to set both dates. and then review for blank grades ( dashes - ) and input zeros as needed in the gradebook.
Additionally, professors can set a Canvas "late policy" that will automatically grade late assignments with either a penalty or a zero. To enable late assignments, the professor would have to adjust the available until date. I personally have not done this step, but it is an option.