<p>I never looked into USC because it's too expensive, but I've been having second thoughts about Berkeley (the school I've SIRed with) and I want to know if I can still SIR with USC.</p>
<p>Your acceptance packet should have stated the deadline to submit a deposit to confirm you would be attending. Usually it is a date in early June or approximately two weeks from the date you received the packet. If you aren't able to locate this date, you can always call admissions and ask them.</p>