Paragraph 7
(1)
An enquiry extends to anything contained in the return, or required to be contained in the return, including anything that relates—
(a)
to the question of whether tax is chargeable in respect of the accounting period, or
(b)
to the amount of tax so chargeable.
This is subject to the following exception.
(2)
If the notice of enquiry is given as a result of an amendment of the return under paragraph 3—
(a)
at a time when it is no longer possible to give notice of enquiry under paragraph 6(2)(a) or (b), or
(b)
after an enquiry into a return has been completed,
the enquiry into the return is limited to matters to which the amendment relates or that are affected by the amendment.