Cal. Rev. & Tax. Code § 4925

If the amount paid by the redemptioner exceeds the amount necessary to redeem the property intended or more than the amount required to be paid for the use of the property pursuant to Chapter 3 of Part 7 of this division the applicant is entitled to a refund of the excess which shall be paid in the same manner as an overcollection of tax is refunded; provided, however, that if the refund is made within 90 days after the date of payment it may be made by the tax collector.