Trusts or partnerships. If a taxpayer determines in good faith that it is a trust or partnership and files a return as such under subtitle A of the Code, and if the taxpayer is later held to be a corporation for the taxable year for which the return was filed, such return shall be deemed to be the return of the corporation for the purpose of section 6501.

Exempt organizations. If a taxpayer determines in good faith that it is an exempt organization and files a return as such under section 6033, and if the taxpayer is later held to be a taxable organization for the taxable year for which the return was filed, such return shall be deemed to be the return of the organization for the purpose of section 6501.

DISC. If a corporation determines in good faith that it is a DISC (as defined in section 992(a)(1)) for a taxable year and files a return as such pursuant to section 6011(c)(2), and if the corporation is thereafter held to be a corporation which is not a DISC for the taxable year for which the return was filed, then—

Such return shall be deemed to be the return of the corporation for the purpose of section 6501.

Such return if filed within the time required by section 6072(b) for filing a DISC return shall be deemed to be filed within the time required by section 6072(b) for filing of a return by a corporation which is not a DISC, and

Interest on underpayment and overpayments allowed by chapter 67 of the Code and additions to the tax, additional amounts and assessable penalties allowed by chapter 68 of the Code, when determined by reference to the time for filing of a return, shall be determined by reference to the time required by section 6072(b) for filing of a return by a DISC.