Whenever a student resubmits an assignment after the due date, It automatically marks the assignment as late. The problem is, they were not late. They did submit the assignment within the due date, they are just seeing the grade they got and are re-submitting that assignment to get a better grade. (While teacher permits.)

Saying this, every time a resubmission button it pushed, I would like canvas to check to see if the original submission was on time, then not make the resubmission late; Rather, have it marked as re-submitted and keep the date of the resubmission. 

There is the problem of students quickly turning in a blank page then latter turning in a completed assignment before the teacher has a chance to grade it. This can be fixed by keeping the original submitted assignment available so the teacher can look and see if the student was truthful in their first submission.