These utilities are useful for manipulating the submit command. The file_filter allows a simple way to reject files that are being submitted and provide feedback to the student indicating why. The deadline or makelateclone commands should be called from a cron or at scheduled job when submissions are being cut off; which command is used will depend on the needs of the course. The unlate command may be useful if making direct use of submit's builtin late-handling capabilities, and submitters gives a list of all students who submitted all time (which, in most courses, is the same as a list of all students who submitted).