Cal. Ins. Code § 10235.50
(a) A policy or certificate shall include a provision that gives the policyholder or certificate holder the right, exercisable any time after the first year, to retain the policy or certificate while reducing coverage and lowering the premium.
(1) The policyholder or certificate holder shall have the option to reduce coverage and lower the premium in the following ways:
(b)
(1) The premium for a policy or certificate that is reduced in coverage shall be both of the following:
(c)
(1) If a policy or certificate contains an inflation protection provision, both of the following shall apply to a reduction in coverage:
(e) If a premium increases, the policyholder or certificate holder shall have the right to retain the policy or certificate while reducing coverage and lowering the premium.
(1) The policyholder or certificate holder shall be offered the option to reduce coverage as provided in subparagraphs (A), (B), and (D) of paragraph (1) of subdivision (a).