(i) consent to and contract for the modification of any of the terms of a mortgage, and note or bond secured thereby, made pursuant to this article for the purpose of obtaining insurance of such mortgage loan by the federal government in order to refinance all or any part of the indebtedness evidenced by such mortgage and note or bonds, or

(ii) satisfy such mortgage loan in order to enable the company to obtain insurance by the federal government of a mortgage loan made for the purpose of refinancing all or any part of the indebtedness evidenced by such mortgage and note or bond. Notwithstanding the provisions hereof, the agency on or after June fifteen, nineteen hundred seventy-six, shall not modify or satisfy a mortgage loan, pursuant to this subdivision one, where the principal amount of the mortgage loan insured by the federal government is less than eighty-five per centum of the principal amount outstanding on the original mortgage loan at the time such original mortgage loan is refinanced, unless such modification or satisfaction is first approved by the New York state public authorities control board created pursuant to article one-A of the public authorities law. 2. In the event that the existing mortgage loan is satisfied pursuant to this section, the agency may in consideration of the issuance of such satisfaction accept a new mortgage and note or bond insured by the federal government in an amount equal to the maximum principal amount of a mortgage loan the federal government will insure or accept the proceeds available to the housing company as a result of the refinancing. 3. In the event that there is residual indebtedness, the housing company shall make and the agency shall accept an instrument evidencing such indebtedness in such form and upon such terms as the agency may approve, provided that such terms are not inconsistent with subdivision two of section twenty of this chapter. 4. Notwithstanding any other provisions of this article where the commissioner has made the findings required in subdivision one of section twenty-six and where a project has been approved pursuant to subdivision five of section twenty-six of this chapter, the agency may make or contract to make a mortgage loan pursuant to subdivision two or three of this section without further findings by the commissioner or further approval by the local legislative body. 5. No company shall accept a mortgage loan to be insured by the federal government made for the purpose of refinancing the existing mortgage loan of a company which shall exceed the amount which can be supported by the income derived from the operation of the project at the rental rate determined by the commissioner that would be necessary to meet all necessary payments to be made by the company, of all expenses including fixed charges, sinking funds, reserves and dividends on outstanding stock as authorized by the commissioner, if the principal amount of the original mortgage loan of the company were to be fully repaid over the term of such mortgage loan by constant and equal payments of principal and interest and if the interest rate on the company's original mortgage loan was eight and one-half percent per annum.