The Restructuring Plan must provide for the section 8 contract to be renewed as project-based assistance, subject to the availability of funds for this purpose, if:

(a) The PAE determines there is a market-wide vacancy rate of 6 percent or less;

(b) At least 50 percent of the units in the project are occupied by elderly families, disabled families, or elderly and disabled families; or

(c) The project is held by a nonprofit cooperative ownership housing corporation or nonprofit cooperative housing trust.