Is it possible to release an assignment if a student submitted by mistake?
Hello Zoltan Blum. By release do you mean erase the first submission? If so then then answer is that no, this cannot be done. For assignments, students may submit the assignment multiple times but from a teacher's standpoint you can always review previous submissions. However, by default when grading using SpeedGrader, the most recent submissions appears and one must select earlier submissions to review them.
I hope this helps but if it doesn't answer your question please let us know!
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