These persons may satisfy their prepayment requirements for the second calendar quarter by making a first prepayment of an amount equal to one-third of the measure of tax liability reported, and a second prepayment of an amount equal to one-half of the measure of tax liability reported, on the return or returns filed for that quarterly period of the preceding year multiplied by the state and local tax rate in effect during the month for which the prepayment is made.
Prepayments shall be made during the quarterly periods designated by the board and during each succeeding quarterly period until further notified in writing by the board.
Ca. Rev. and Tax. Code § 6471