80(1)An assessment under paragraph 78 or 79 of an amount of levy due for any accounting period—U.K.
(a)shall not be made more than two years after the end of the accounting period unless it is made within the period mentioned in sub-paragraph (2); and
(b)subject to sub-paragraph (3), shall not in any event be made more than three years after the end of that accounting period.
(2)The period referred to in sub-paragraph (1)(a) is the period of one year after evidence of facts sufficient in the Commissioners’ opinion to justify the making of the assessment first came to their knowledge.
(3)Subject to sub-paragraph (4), where levy has been lost—
(a)as a result of any conduct for which a person has been convicted of an offence involving fraud,
(b)in circumstances giving rise to liability to a penalty under paragraph 55 (failure to notify of registrability etc.), or
(c)as a result of conduct falling within paragraph 98(1) (evasion),
that levy may be assessed under paragraph 78 or 79 as if, in sub-paragraph (1)(b) above, for “three years" there were substituted “twenty years".
(4)Where, after a person’s death, the Commissioners propose to assess an amount of levy as due by reason of some conduct of the deceased—
(a)the assessment shall not be made more than three years after the death; and
(b)if the circumstances are as set out in sub-paragraph (3)—
(i)the modification of sub-paragraph (1) contained in that sub-paragraph shall not apply; but
(ii)any assessment which (applying that modification) could have been made immediately after the death may be made at any time within three years after it.
(5)Nothing in this paragraph shall prejudice the powers of the Commissioners under paragraph 78(4).