Commitments made by a local agency in connection with contracts whose costs are to be charged to operating expense or replacement reserve shall be recorded in account 1500A, Incompleted Contracts—Management, and account 2400A, Contract Awards—Management. The method of recording contract awards, contract changes and partial payments is similar to that described in sections 1646-5.2, 1646-5.3 and 1646-5.4 for the development period. At the end of each reporting period, a journal voucher shall be prepared charging the appropriate operating expense account and crediting account 2119, Sundry Accounts Payable, and also charging account 2400A. Contract Awards—Management, and crediting account 1500A, Incompleted Contracts—Management, with the total amount of any unpaid approved periodic estimates for partial payment on hand.