Beginning with the date of substantial completion, all project revenue shall be deposited into the administration fund and all expense chargeable to project revenues shall be paid therefrom. The opening of the administration fund at the beginning of the initial operating period, the operation of the fund during that period, the setting up of the income and expense analysis ledgers and the tenants' accounting system, the closing of the books at the end of the initial operating period, the transfer of funds between the development and administration funds to adjust for net income or deficit of the initial operating period, advances by the development fund, prepaid expenses and payable, change and petty cash funds, etc., have been described in Subpart 1646-6, to which references should be made.