How many years of undergrad can I skip?

Colleges & Universities University of California - GENERAL
2

I think all of the CA public colleges limit students to 70 (semester) units - here’s the UC policy.

https://admission.universityofcalifornia.edu/admission-requirements/transfer-requirements/preparing-to-transfer/transfer-credit.html

that’s a little over 2 years with a typical load - so you could probably earn a BA/BS in 2 additional years.

As a recent high school grad, you will be evaluated as a freshman applicant.

If i might ask, what’s the hurry?