If you're talking about moving in to the dorms, or some other form of housing in which he has a contract and a start date, no, they will not let you move in before your contract has started. If your contract starts July 21, they will not let you move in on July 20 (well, some place do, like if you have to fly in or in other extreme circumstances but "I just want to move in early" doesn't cut it).

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So when you're happy (Hurray!), or sad (Aw!),
Or frightened (Eeek!), or mad (Rats!)
An interjection starts a sentence right.