No refund shall be approved by the board after three years from the last day of the second month following the close of the month for which the overpayment was made, or, with respect to determinations made under Article 3 or 4 of Chapter 4 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. 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.