To look up the dates and deadlines in terms of courses, i.e. last day the Program Coordinator can enroll students into department-consent required courses, etc., you can do so at the Registrar's website: https://registrar.arizona.edu/dates-and-deadlines.
If you miss the deadline, then a Change of Schedule form must be submitted by the student to Registrar which requires the instructor's and Dean's signatures: https://registrar.arizona.edu/records-enrollment/enrollment/change-sche…
To look up the dates and deadlines in terms of requirements for graduation approval, you can do so at the Graduate Student Academic Services website: https://grad.arizona.edu/gsas/degree-requirements/important-degree-date…