171(1) If a transfer pricing notice is given to a person (“T”), T may amend T's tax return for the purpose of complying with the notice at any time before the end of the period of 90 days beginning with–
(a)the day on which the notice is given, or
(b)if T appeals under section 170 against the decision to give the notice, the day on which the appeal is finally determined or abandoned.
171(2) If a transfer pricing notice is given in the case of any tax return, no closure notice may be given in relation to that tax return until–
(a)the end of the period of 90 days specified in subsection (1), or