Normative study period

Normative study period
 

Are my sentences natural English?:

-Students exceeding the normative study period will receive the email notification from Bursary around late-September, as their fees depend on the units of courses registered. A student in arrears shall be subject to fines. Unless written approval is given by the University to defer payment, a student in arrears, whether in part or in full, or who has outstanding fees/fines unpaid, shall be withheld from University services such as course registration and add/drop, application for transcript and certifying letter, graduation assessment, until all outstanding fees/fines are settled.

I would use standard instead of normative. ...will receive an email notification from the bursar (or the department of the bursar) advising the student of additional amounts due..
Unless written approval is given by the university to defer payment, students in arrears are subject to restrictions from course registration, applications for transcripts, letters of certification and graduation assessment.

Thank you~