Can you cancel SIR?

<p>My brother got accepted into UCI and is waitlisted for UCSD. He wants to get into UCSD but he won’t find out until June 1st, and that is the deadline to accept UCI. </p>

<p>My question is: can he just sign the SIR with UCI now? And if he gets accepted into UCSD then he can cancel the SIR with UCI. Is that possible? UCSD is his first choice and he really wants it. </p>

<p>Thanks in advance!</p>

<p>Yes and yes.</p>