Para 44 (my underlining ) says
A discovery assessment for an accounting period for which the company has delivered a company tax return, or a discovery determination, may be made if at the time when the Inland Revenue—.
(a)ceased to be entitled to give a notice of enquiry into the return, or.
(b)completed their enquiries into the return,.
they could not have been reasonably expected, on the basis of the information made available to them before that time, to be aware of the situation mentioned in paragraph 41(1) or (2).
So clearly as HMRC
(I) Had validly opened an enquiry
(ii) Had clearly been of the view before closing the enquiry that an underassessment situation existed
(ii) issued a closure notice in relation to the enquiry
it is impossible for them to say that there was a discovery of the underassessment position (for Para 41) only after the they closed their enquiry. So clearly Para 44 would restrict their ability to make a discovery assessment and the information provided by the company during the enquiry would be information provided or made available to HMRC under Para 44(2)
Additionally they have issued a closure notice and therefore any adjustments or assessment to be made must accord with the closure notices content. If the closure notice says no adjustments were necessary then clearly no assessment is required and the enquiry has been closed accordingly.
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