There's no limit or guarantee for the number of reviews you can receive on your case study.
Every time you ask for a review, your case study will be available on the Reviews page for others. There is no limit on the number of reviews you can receive on a case study. However, to ensure everyone gets feedback on their work, the list you see on the Reviews page is ordered by the number of reviews a case study has. So if you already got three reviews on a certain case study, other people's case studies with no reviews will appear before yours.