Everyone who received a deferred acceptance in years prior eventually got a call saying there was room for them in the class starting that year. Essentially they start calling the deferred people prior to calling the wait list people once people drop/don't pay deposits (look at years prior to 2017 class threads) . There will be a ton of movement usually around early June that continues until schools commences. Some people actually take the deference and some who got accepted choose to defer as well.