16(1)An officer of Revenue and Customs may enquire into the return if, within the time allowed, the officer gives notice to the filing member of the officer's intention to do so.U.K.
(2)The time allowed is—
(a)if the return was submitted on or before the submission date, up to the end of the period of 12 months after the submission date;
(b)if the return was submitted after the submission date, up to and including the quarter day next following the first anniversary of the day on which the return was delivered;
(c)if the return is amended under paragraph 14, up to and including the quarter day next following the first anniversary of the day on which the return was amended.
(3)The submission date is the day ending the period for submission of the return referred to in paragraph 13(8) (or the longer period referred to in paragraph 13(10) where applicable).
(4)The quarter days are 31 January, 30 April, 31 July and 31 October.
(5)A notice under this paragraph is referred to in this Part of this Schedule as a “notice of enquiry”.
(6)A return that has been the subject of one notice of enquiry may not be the subject of another, except one given in consequence of an amendment of the return.