If this is you, my condolences. I’m sure that’s wasn’t the outcome you were hoping for.
For many schools, each month they will ask if you are still willing to be on the waitlist, and each month they evaluate the waitlist. So you could get accepted anytime between now and class starting.
It’s a good idea to consider why you might have landed there. If your test score is subpar then this is a strong hint to retake. If that’s not the case, get some holistic feedback on your application to see if it aptly demonstrates leadership, teamwork, ability to contribute and clear, realistic goals. Then, create a strategy for creating an update effort. Address whatever shortcomings were identified.
So if you have a shallow leadership record in the workplace or community, this might signal for you to step up your commitments in those areas; get a board position if possible. Then submit an update letter to highlight that in a couple months after you’ve demonstrated impact.
It is unwise to send them continuous updates which will show lack of judgment. However, it is wise is to be strategic about using this time as an opportunity to reposition yourself. At the same time, make sure to submit other applications! Worrying won’t help so continue to create options and possibilities.