Ask the admission officer for some extension. give them some excuse. actually they understand that every student would applying for several schools, so they won't dig into the details. Some schools will give one or two weeks extension, others won't. It depends on which round you applied.
Anyway, just send an inquiry email politely, you have nothing to lose.
If the school refuse to give any extension, you still could submit the deposit before deadline. Acutally, I got the extension from a school, so I know it works.
Anyway, it's just experience for sharing. You can make your own judgement.