I have a professor who has set up a single assignment for weekly response papers. Students were meant to make a new submission every week - that way, he can have all of a given student's response papers together, and scroll between them using the Multiple Submission dropdown menu in the Speedgrader.
Unfortunately, it appears that almost all of the student submissions have been lost. Only one of his 30-or-so students still has multiple submissions available to look at in the SpeedGrader, and many have no submissions at all, although he claims that until recently he had access to all of his students' submissions.
I know that there is not supposed to be any way to delete/remove/unsubmit submissions in Canvas, so this is very confusing and concerning. We have checked the undelete page and the professor's course activity, and we can't find anything that looks like he deleted the assignment or did anything of that sort. Does anyone have any ideas of what could have happened, or any suggestions? We will be contacting Canvas support to see if we can roll the course back to a previous version, but we'd like to know what happened as well.