On notify_on_submit

Is there a time rule for the notification? For example, I think it won't be necessary for notification before deadline, to notify the sa, And it is more important to notify them about his/her deadline when all assignment should be graded.

Start by locating the notify_on_submit setting and the notification behavior it controls. Clarify whether notifications should be sent before deadlines or when grading is complete, then confirm the intended timing and acceptance criteria with the maintainers before identifying the relevant implementation and tests.

Written by the indexing model from the issue text.