24 C.F.R. § 886.129

(a) Availability of units for occupancy by Eligible Families. During the term of the Contract, an owner shall make available for occupancy by eligible families the total number of units for which assistance is committed under the Contract. For purposes of this section, making units available for occupancy by eligible families means that the owner: (1) Is conducting marketing in accordance with § 886.121; (2) has leased or is making good faith efforts to lease the units to eligible and otherwise acceptable families, including taking all feasible actions to fill vacancies by renting to such families; and (3) has not rejected any such applicant family except for reasons acceptable to HUD. If the owner is temporarily unable to lease all units for which assistance is committed under the Contract to eligible families, one or more units may be leased to ineligible families with the prior approval of HUD. Failure on the part of the owner to comply with these requirements is a violation of the Contract and grounds for all available legal remedies, including specific performance of the Contract, suspension or debarment from HUD programs, and reduction of the number of units under the Contract as set forth in paragraph (b) of this section.

(b) Reduction of number of units covered by Contract. HUD may reduce the number of units covered by the Contract to the number of units available for occupancy by eligible families if:

(1) The owner fails to comply with the requirements of paragraph (a) of this section; or

(2) Notwithstanding any prior approval by HUD to lease such units to ineligible families, HUD determines that the inability to lease units to eligible families is not a temporary problem.

(c) Restoration. HUD will agree to an amendment of the Contract to provide for subsequent restoration of any reduction made pursuant to paragraph (b) of this section if:

(1) HUD determines that the restoration is justified by demand;

(2) The owner otherwise has a record of compliance with his or her obligations under the Contract; and

(3) Contract and budget authority are available.

(d) Applicability. Paragraphs (a) and (b) of this section apply to Contracts executed on or after October 3, 1984.

(e) Termination of assistance for failure to establish citizenship or eligible immigration status. If an owner subject to paragraphs (a) and (b) of this section is required to terminate housing assistance payments for the family in accordance with part 5, subpart E, of this title because the owner determines that the entire family does not have U.S. citizenship or eligible immigration status, the owner may allow continued occupancy of the unit by the family without Section 8 assistance following the termination of assistance, or if the family constitutes a mixed family, as defined in part 5, subpart E, of this title, the owner shall comply with the provisions of part 5, subpart E, of this title concerning assistance to mixed families, and deferral of termination of assistance.