1st AD from U Mich, Ann Arbor 结束失学

申请的PhD, 被Masters录了, 就是学费有点略贵啊。。想问一下邮件说的：“If you would like to accept our
offer of admission into our Master’s program, please send a message to me-gradapplication@
umich.edu stating that you would like your program changed from Ph.D. to MSE. A few
days after you notify us of your intent, the Horace H. Rackham School of Graduate Studies will send
you a formal notification acknowledging your admission to our Master’s program.”
意思是我发邮件同意转MSE之后，只是作为我转MSE的证明，还是说会同时算作我accept offer？
还有就是不知道什么时候是接受的deadline？ 多谢各位！