Unless the lease had other terms written in, California generally allows landlords to continue to charge rent until the unit is rented again (or the end of the lease term).
I know my current landlord is going to be excited about me leaving in a month, as rent had gone up about $1,300 a month in this area over the last two years, but my increase are capped.
"In the event the lease is broken during the middle of the term, and the applicant did not pay a year up front due at lease signing, the lease break fee is $1,200.00 made payable to the Shareholder. The penalty fee is charged by the coop board to the Shareholder due to the lease break. Lessees are immediately relieved of his or her contractual obligations to the Shareholder & coop upon successful take over by the next Lessee(s) identified by the broker, and is board approved for move in."
Then again, if the current tenant has a lead on someone to potentially take over the lease and become a long-term tenant, then everybody wins.