Effect on variances within park and notice of same. Applicants for variances or special permit shall be promptly notified by the Zoning Board of Appeals that the Secretary of the Interior is authorized to withdraw the suspension of his authority to acquire, by condemnation, property which is made the subject of a variance or exception that, in his opinion, fails to conform or is in any manner opposed to or inconsistent with the purposes of the Cape Cod National Seashore. The Secretary of the Interior shall be given notice by the Zoning Board of Appeals of all applications or petitions made for variances or special permit to the bylaws for the Seashore District, and he shall be provided notice by the Planning Board of all applications for building permits involving the Seashore District: all such notices to be given within seven days of receipt of the applications or petitions. Subsequently, to meet the requirements of the Act of Congress of August 7, 1961, the Secretary shall be given notice by the appropriate board of any variance, or exception, or building permit granted or denied for within the Seashore District.