“The real question, therefore, is whether the erroneous assumption on the part of both parties to the agreements… was of such a fundamental character as to constitute an underlying assumption without which the parties would not have made the contract they in fact made, or whether it was only a common error as to a material element, but one not going to the root of the matter and not affecting the substance of the consideration.”
“that the matter as to which the mistake existed was an essential and integral element of the subject-matter of the contract, or it was an inevitable inference from the nature of the contract that all the parties so regarded it.”
“28A(2) A ... final closure notice must state the officer’s conclusions and– (a) ... (b) make the amendments of the return required to give effect to his conclusions.”
“Section 28A(2)(b) requires the amendment of the return to be made by the closure notice itself; not merely by an officer of HMRC. So, unless incorporated by reference, Mrs Cook’s amendment of the online return cannot itself satisfy the words of the sub-section.”