Students are savvy enough to submit blank documents and feign the appearance of work completion. This feature of un-submitting a piece of work IS available but only when the assignment is completed on a teacher-distributed template with multiple student copies. However, when students do their own uploading of a doc from their drive/resources, it is not available.
Students being allowed to submit work that is blank without being able to send it back for completion gives misinformation in reporting work completion to parents as well as staff. This has to be a priority - if this is a learning management system that heralds communicating to students, parents, staff - this is a must-fix.