This is from Ms. Sun’s UC blog- a great source of info for the UC’s:
http://■■■■■■■■■■■■/home/uc-freshman-application-timeline/#decisions
Appeal Writing Guidelines
Remember, telling the admissions office that they made a huge mistake is not
going to help your case. For your appeal to be considered, you must prove
that you are a much stronger candidate than what was presented in your
application. Specifically, you must provide new and compelling information that was not previously available to the admissions office.
Your need to stay in a particular geographical area, in itself, does not constitute grounds for an appeal. Any hardship in relocating must be accompanied by other new and compelling information for your appeal to be considered. Similarly, changing your major, in itself, is not sufficient grounds for an appeal; additional new and compelling information must be present for your appeal to be considered.
Examples of new and compelling information may include extraordinary hardship or exceptional talent. You can discuss these things on your appeal as reasons for the UCs to reconsider you. Make sure you describe exactly how the exceptional talent qualifies you for UC admissions or how the hardship prevented you from achieving academically. The focus of your appeal should be on why you are an excellent candidate for the UCs and why the UCs should be interested in you, not why your hardship is horrible or how much you love a particular UC campus and must go there. State your case concisely (one page appeal is ideal but two pages are acceptable) and don’t exaggerate or try to be dramatic. Keep in mind that the acceptance rate on appeal is less than 10% for most UCs and less than 3% for Berkeley and UCLA. Please visit Appeal or Free Service for additional service options.