With respect to a taxable year beginning after December 31, 1948, and ending before October 1, 1956, the income tax return of any corporation organized under the China Trade Act of 1922 (15 U.S.C. ch. 4), as amended, shall not become due until December 31, 1956, provided that during any such taxable year conditions in China have been generally so unsettled as to militate against the normal commercial operations and corporate activities of such corporation. However, the postponement of the due date shall not apply to an income tax return for any such taxable year if:

The books of account and business records are available so as to permit the filing of a proper return, and the corporation has otherwise been in a position to carry on its commercial operations and corporate activities and to make a proper distribution of its earnings or profits, if any, so as to permit the certification required by section 941(b); or

All the commercial operations and corporate activities of such corporation have been carried on in Hong Kong, Macao, or Taiwan (Formosa).

Notwithstanding the provisions of paragraph (a) (1) or (2) of this section, the postponed due date referred to in this section will apply if a corporation satisfies the Commissioner that special circumstances exist, related to the unsettled conditions in China, which warrant such postponement.

The postponed due date provided for in this section is expressly subject to the power of the Commissioner to extend, as in other cases, the time for filing the income tax return. See section 6081 and the regulations thereunder.