If you interviewed at every SoCal program, you wouldn't need to apply elsewhere, there are enough spots to go around and the programs vary in how difficult it is to get in. If your only objective is to end up SOMEWHERE in southern California, you've got nothing to worry about. Your backup could be staying at your current med school, don't waste your time and money running all over the country doing unnecessary interviews. Every year, applicants spend thousands travelling the country but when it's time to sit down and make your actual rank list, location usually ends up trumping all the other BS for most people.