Cal. Code Regs. tit. 10 § 2232.23
Written proof of loss must be furnished to the insurer, in case of claim for loss for which this policy provides any periodic payment contingent upon continuing loss, within 90 days after the termination of the period for which the insurer is liable, and in case of claim for any other loss, within 90 days after the date of such loss. Failure to furnish such proof within the time required shall not invalidate nor reduce any claim if it was not reasonably possible to give proof within such time, provided such proof is furnished as soon as reasonably possible and in no event, except in the absence of legal capacity of the employee, later than one year from the time proof is otherwise required.
Instructions
In any policy which provides both benefits payable periodically and benefits payable when they occur or as they accrue, the insurer shall make clear by the terms of the policy which benefits are to be paid as they accrue or when they occur. This may be done in any lawful manner. Either of the two following ways would be acceptable. First, the insurer may specify in the benefit clauses themselves those benefits which will be paid periodically and those which will be paid as they accrue or when they occur, in which case no change in the language of the uniform provision is required. Second, the insurer may, in lieu of the phrase "in case of claim for loss for which this policy provides any periodic payment contingent upon continuing loss," identify by name or description or by place reference the benefits which will be paid periodically, and leaving unchanged the provision that as to any other loss proof is required within 90 days after the date of the loss. (Ins. C. 10350.7.)
Cal. Code Regs. Tit. 10, § 2232.23