A waitlist is still an open "maybe," not a soft rejection, and plenty of applicants come off waitlists every year, sometimes just weeks before orientation begins. Movement typically picks up noticeably after the AAMC's national commitment deadline in the spring, once admitted students start choosing between their offers and dropping seats elsewhere.
Follow each individual school's stated policy on sending updates — some welcome them, some explicitly discourage unsolicited contact. If a school welcomes updates, send a letter of intent or a substantive update letter with genuinely new information, not just a restatement of continued interest. After that, the honest advice is to keep living your life rather than refreshing the applicant portal every hour.