California Code, Revenue and Taxation Code - RTC § 276.2

(a) If property becomes eligible for the disabled veterans' exemption as described in Section 205.5 after the lien date, and an appropriate application for that exemption is filed on the later of 90 days after the date on which the property became eligible or on or before the next following lien date, there shall be canceled or refunded the amount of any taxes, including any interest and penalties thereon, levied on that portion of the assessed value of the property that would have been exempt under a timely and appropriate application.

(b) The entire amount of the exemption applies to any property tax assessment, including a supplemental and escape assessment, that was made and that served as a lien against the property. The exemption amount shall be appropriately prorated from the date the property became eligible for the exemption.