Yes, you can do as many cases as many times as you want during your subscription period. After completing each case, you will be given a grade. If you do 10 attempts on one case, you will be given 10 different feedback scores. All attempts and their scores will be saved for your review. See the image below: at the grading menu, they will be listed by the time of each attempt. You can click on each attempt to view your feedback and score.