Property restriction. All AFFH units must be restricted using a document such as a declaration of restrictive covenants, in recordable form acceptable to the Village Attorney, which shall ensure that the AFFH unit shall remain in perpetuity, subject to affordable regulations except as hereinafter provided. Among other provisions, the covenants shall require that the unit be the primary residence of the residential household selected to occupy the dwelling unit. Upon approval, such declaration shall be recorded against the property containing the AFFH unit prior to the issuance of a certificate of occupancy for the dwelling unit. These property restrictions notwithstanding, the covenants may allow a property owner, no earlier than 50 years from the date of initial certificate of occupancy for rental properties and from date of original sale for ownership units, to seek a release from such restrictions by request to, and the affirmative approval of, the Briarcliff Manor Board of Trustees.