(a)

(1) For persons required to file returns on other than an annual basis, except as provided in subdivision (

b) no refund shall be approved by the board after three years from the last day of the month following the close of the quarterly period for which the overpayment was made, or, with respect to determinations made under

Article 2 (commencing with

Section 6481),

Article 3 (commencing with

Section 6511), or

Article 4 (commencing with

Section 6536) of

Chapter of this part, after six months from the date the determinations become final, or after six months from the date of overpayment, whichever period expires the later, unless a claim therefor is filed with the board within that period.

(2) For persons required to file returns on an annual basis, except as provided in subdivision (

b) no refund shall be approved by the board after three years from the last day of the calendar month following the one-year period for which the overpayment was made, or with respect to determinations made under

Article 2 (commencing with

Section 6481),

Article 3 (commencing with

Section 6511), or

Article 4 (commencing with

Section 6536) of

Chapter 5, after six months from the date the determinations become final, or after six months from the date of overpayment, whichever period expires the later, unless a claim therefor is filed with the board within that period. No credit shall be approved by the board after the expiration of that period unless a claim for credit is filed with the board within that period, or unless the credit relates to a period for which a waiver is given pursuant to

Section 6488. (

b) A refund may be approved by the board for any period for which a waiver is given under

Section if a claim therefor is filed with the board before the expiration of the period agreed upon.