Immediately following the close of each calendar quarter, there shall be withdrawn from the administration fund and deposited in the reserve fund, the amounts set aside for vacancy and collection loss, painting and decorating, and replacements reserves computed in accordance with Subpart 1647-4. If, at the end of the calendar quarter, the amounts computed for the specified reserves should be negative figures, a corresponding amount shall be withdrawn from the reserve fund and deposited in the administration fund. Individual transfers of funds with respect to each reserve are not, however, prescribed and it is recommended that lump sum transfers, reflecting the net amount to be transferred either way, be made. Interest on reserve fund investments shall be deposited in the reserve fund when received.