test and make the identifications required under this subsection at the following times during any continuous period the taxpayer simultaneously holds 1 or more derivatives with respect to an underlying investment and 1 or more portions of the underlying investment: (i) The beginning of the period. (ii) Immediately after the taxpayer (during such period)— (I) enters into another derivative with respect to the underlying investment or acquires an additional amount of such underlying investment, or (II) terminates or transfers 1 or more derivatives with respect to the underlying investment or sells or exchanges any portion of the underlying investment, except that no testing and identification shall be required under this subclause with respect to any such transaction if the taxpayer does not have an investment hedging unit with respect to the underlying investment immediately before such transaction. (iii) Such other times during such period as the Secretary may prescribe by regulations or other guidance. (B) No other times for testing Except as provided by the Secretary, there shall not be taken into account for purposes of this part any testing and identification done by the taxpayer with respect to an underlying investment at a time other than the times required under subparagraph (A). (4) Manner A taxpayer shall be treated as timely making the identifications required under this subsection if derivatives with respect to, and portions of, an underlying investment are clearly identified as part of (or as not part of) the investment hedging unit for purposes of this paragraph before the close of the day on which the identification is required (or such other time as the Secretary may prescribe). (5) Treatment of incorrect identification of hedging transactions The Secretary shall prescribe regulations to properly characterize any income, gain, expense, or loss arising from any derivative or underlying investment which is incorrectly identified under paragraph (2) as being part of, or not being part of, an