Rev. & Tax. Code, § 4985.3

(a) Notwithstanding Section 2610.5, in the case of cancellations made to the roll pursuant to Section 1646.1, where a taxpayer has failed to pay an amount of tax computed upon assessed value that is the subject of a pending assessment appeal, the relief from penalties shall apply only to the difference between the county board’s final determination of value and the value on the assessment roll for the fiscal year covered by the application. For purposes of this section, “county board” means either a county board of supervisors that meets as a county board of equalization or an assessment appeals board.

(b) The county board shall cause notice of the requirements of this section to be mailed to each taxpayer or to be presented to each taxpayer upon filing an application for reduction in assessment with the county board if that taxpayer will be impacted by the penalty provisions of this section.

(c) For any taxpayer who has paid at least 80 percent of the amount of tax finally determined due by the county board within 60 days of mailing or presentation of the notice prescribed in subdivision (b), the tax collector shall accept payment of the balance of the tax due without penalties or interest.

(d) This section shall apply only to those properties upon which an application for reduction in assessment is pending before the county board on the effective date of the act adding this section or those applications for reduction in assessment that are filed with the county board after the effective date of the act adding this section.

(e) This section shall only become operative if the board of supervisors of a county, with the approval of the county’s tax collector and the county’s auditor, adopts a resolution or ordinance approving this section.