如题，今天收到一封信件，内容如下:
Thank you for your application and your time for interview for the admission
to our PhD Programmes 2017-18.
We are pleased to inform that you have been recommended for admission with
financial support. Kindly note that this email
serves as a notification that you are in our nomination list only, and it
does not automatically imply that your admission has been confirmed.
Confirmation of admission offer is subject to verification of admission
documents by the Graduate School of The University of Hong Kong (HKU).
信件最后要求我在3/3前做决定，内容如下:
In this connection, please notify us in advance whether you incline to choose
to study in our School at The University of Hong Kong, or you have already
decided not to, by sending an email by March 3, 2017
(this Friday) you have made such a decision.
因为我还在等一所我最想读的学校的offer,如果那家没上我一定会去念HKU,请问
如果我先回复接受HKU,之后有变动还可以更改意愿吗?
先感谢诸位的回答，如果有不符板规我会自行删除，谢谢。