(A) In the case of loans under sections 1484 and 1485 of this title approved prior to the effective date of this paragraph with respect to which rental assistance is provided, the rent for tenants receiving such assistance shall not exceed the highest of (i) 30 per centum of monthly adjusted income, (ii) 10 per centum of monthly income, or (iii) if the person or family is receiving payments for welfare assistance from a public agency, the portion of such payments which is specifically designated by such agency to meet the person’s or family’s housing costs.
(B) In the case of a section 1485 loan approved prior to the effective date of this paragraph with respect to which interest credits are provided, the tenant’s rent shall not exceed the highest of (i) 30 per centum of monthly adjusted income, (ii) 10 per centum of monthly income, or (iii) if the person or family is receiving payments for welfare assistance from a public agency, the portion of such payments which is specifically designated by such agency to meet the person’s or family’s housing costs, or, where no rental assistance authority is available, the rent level established on a basis of a 1 per centum interest rate on debt service.
(C) No rent for a unit financed under section 1484 or 1485 of this title shall be increased as a result of this subsection or other provision of Federal law or Federal regulation by more than 10 per centum in any twelve-month period, unless the increase above 10 per centum is attributable to increases in income which are unrelated to this subsection or other law, or regulation.