Section applicable to (1) any requirement to furnish information under this section if the time for furnishing such information is after Nov. 5, 1990, (2) any requirement under subsec. (a) of this section to maintain records which were in existence on or after Mar. 20, 1990, (3) any requirement to authorize a corporation to act as a limited agent under subsec. (d)(1) of this section if the time for authorizing such action is after Nov. 5, 1990, and (4) any summons issued after Nov. 5, 1990, without regard to when the taxable year (to which the information, records, authorization, or summons relates) began, see section 11315(c) of Pub. L. 101–508, set out as an Effective Date of 1990 Amendment note under section 6038A of this title.