Such proceeds and investments in escrow or trust shall be in an amount at the time of issuance of such refunding bonds which is certified by a certified public accountant licensed to practice in this state to be sufficient to meet the requirements of subdivision (a) or paragraph (b) of this section.
(a)
Such proceeds and investments, together with any interest or other gain to be derived from any such investment, shall be in an amount at least sufficient to pay (i) the principal of and interest and redemption premiums, if any, on the refunded bonds as they become due or at designated dates prior to maturity (in
connection with which the legislative body has exercised or has obligated itself to exercise a redemption privilege on behalf of the local agency) and (ii) the designated costs of issuance of the refunding bonds, or
(b)
Such proceeds and investments, together with any interest or other gain to be derived from any such investment, shall be in an amount at least sufficient to pay (i) the principal of and interest and redemption premiums, if any, on the refunding bonds prior to the maturity of the bonds to be refunded or prior to a designated date or dates before the maturity of the bonds to be refunded (in connection with which the legislative body has exercised or has obligated itself to exercise a redemption privilege on behalf of the local agency), (ii) the principal of and any redemption premiums due on such refunded bonds at maturity or at said designated date or dates and (iii) the designated costs of issuance of the refunding
bonds.