At the beginning of your course, the instructor will send you a schedule broken into 3-week intervals. Each of these milestones will indicate how far into the course you should be by that date. These milestones are crucial in setting a pace for successful completion of the course, and they need to be followed in order to remain in the Open School program.
You have as much flexibility within these milestone intervals as you need, and you are permitted (and encouraged) to accelerate your progress ahead of the schedule. If you complete your course early, you will be able to write the exam early as well and move on to your next Open School course!