Notwithstanding any other provision of law, for any project for which an owner gives preference in occupancy to elderly families pursuant to section 13611 of this title, such owner shall (subject to sections 13613, 13614, and 13615 of this title) reserve units in the project for occupancy only by disabled families who are not elderly or near-elderly families (and who have applied for occupancy in the housing) in the number determined under subsection (b).