3(1)A person who has delivered a return may amend the return by notice to an officer of Revenue and Customs.U.K.
(2)The Commissioners for Her Majesty's Revenue and Customs may require that notices under this paragraph—
(a)are in a specified form, or
(b)contain specified information.
(3)An amendment under this paragraph must be made by the end of the next chargeable period after the chargeable period to which the return relates (but see the exception that follows).
(4)If a return is delivered on or after 1 January in the chargeable period next after that to which it relates, the latest time for amending the return under this paragraph is the end of the period of 3 months after the day on which the return is delivered.