Blackboard submissions cannot generally be edited or deleted once they are submitted, even if the deadline hasn't passed. However, students can save their work as a draft before submitting it. This allows them to make changes without actually submitting the assignment. Importantly, if a student leaves an assignment as a draft, Blackboard will automatically submit it when the due date arrives.
It's important to note that this rule generally applies to most assignments. The only exception is Discussion Forums, where students might be able to edit their posts if the instructor has enabled this option. However, even in Discussion Forums, responses are not automatically submitted.
If students want to save a draft and edit their submission before the due date, they have to click Save and Close instead of Submit.

If they check their Gradebook, they will be able to see that the submission is currently saved as a draft.

Once they need to edit or want to submit their attempt, they can go to the assignment again and simply click Continue attempt.
