by John Provasnik.
Richard,
That makes sense. And the class logs seem to back up what you are saying. If a child goes back into that assignment, deletes the old submission, and uploads a new submission, the date in the zip file will remain the date of the original submission, whereas the date in Moodle will update. This makes sense. However, sometimes this isn't the case, such as when a date appears as tomorrow's date.