Waitlist timeline:
2022: Some admits after May 1, some denials on June 9 and waitlist closed on June 18. 2022.
2023: Small number of admits on Monday April 24, 2023. Rare admit May 3. More admits on Friday May 5. Few admits May 18 and June 6. Few admits around June 18 including CS. Admits on June 30 but for Winter quarter (appears to be a new option for Freshman admits).
If spots open up before the May 15 SIR deadline, then they can pull from the waitlist.
UCSC Waitlist discussion thread is here: https://talk.collegeconfidential.com/t/uc-santa-cruz-freshman-class-of-2028-waitlist-appeal-discussion/