My question involves a security deposit in the State of California for an apartment rental.

There are three dates involved:

Tenant served a 30 Day Notice to Vacate on 3-1-10, responsible for rent through 3-31-10.

Tenant moved possessions out on 3-15-10.

Tenant returned keys (giving landlord possession) on 3-23-10.

What day do you start counting the 21 days to be in compliance with the law?

Thank you!