The only UC campus that has confirmed a date is UCB for March 30.
UCLA has historically posted decisions on the 3rd Friday of March which would be March 17 ( not confirmed).
None of the other campuses have given specific dates and last year only UCSB besides UCB stated a specific decision date but no date has been confirmed yet.
2022 Decision dates:
UCB: Early admits on Feb 11, 2022. All other decisions on March 24.
UCLA: Friday March 18 at 5 PM PST.
UCSD: Friday March 18 around 4:30 PST
UCSB: March 22, 2022 around 2:15 PM PST
UCI: CHP admits March 11, 2022. The rest of the Decisions on March 18, 2022.
UCD: Friday March 11, 2022
UCSC: 1st Wave starting Friday February 25th. 2nd Wave March 15th.
UCR: Rolling Waves starting March 2, 2022
UCM: Rolling Waves starting March 1, 2022