62db5789_Known_Issues__Affected_Users
[Current Issue] Assignments: The Allow deleting option does not function as expected. If it's set to No a student can still delete their file/s and re-upload new ones. [Status] This issue is currently with Moodle HQ. [Affected Users] 
Teaching staff using Assignments Be aware that students will be able to delete files and upload new files even if the Allow deleting otpion is set to No.