edX courses are either self-paced or instructor-paced. Your experience with due dates and their flexibility will differ depending on the course's pacing type. All course sessions have end dates. Read more about where to find your course's due dates.
Instructor-paced
Instructor-paced courses have a fixed schedule. Course materials may be published periodically, and there may be fixed due dates. After an assignment's due date passes, you will no longer be able to complete the assignment. If you join the course late, you cannot make up any due dates you missed, but you may still be able to earn a passing score. Check your course's syllabus, calendar, or welcome module for information about the course schedule and grading policy.
Self-paced
Self-paced courses may feature suggested due dates. These due dates are personalized suggestions based on the date you first enrolled to help you plan and pace your studies. You can submit assignments or exams any time up until the final end date of the course. The final end date is fixed and not shiftable or flexible. Read more about the suggested schedule.
Note: the suggested schedule does not apply to the final course end date or open response assessments such as peer-reviewed essay assignments. These due dates are fixed by your instructor and they can't be shifted or extended.