关于NEU的占坑费

刚才收到了neu催交占坑费的邮件，里面说We wanted to let you know that there is not much time to reserve a space on the Boston campus at Northeastern University.这句话是什么意思…难道即使我在占坑费ddl之前交了费用也有可能把位置让给别人吗…?还是其实我只需要在3.31的ddl之前任何一天交了费用就能给我留住位置？