A copy of the certification issued to an excluded bank under section 552(b)(2) and Sec. 1.552-4 shall be filed with, and made a part of, the income tax return for the taxable year of each United States shareholder of such foreign corporation, if he has been a shareholder of such corporation for any part of such year. If the certificate has not been issued at the time the return of the United States shareholder is filed, the shareholder shall compute the tax on his return by treating the bank as a foreign personal holding company. If a certificate is issued after the return is filed, the United States shareholder may file a claim for refund or an amended return, and shall attach thereto a copy of the certification.