(1)This section applies if an officer of Revenue and Customs thinks—
(a)that there is a section 946 payment which should have been included in a return under this Chapter and which has not been so included, or
(b)that a return under this Chapter is otherwise incorrect.
(2)An officer of Revenue and Customs may make an assessment, to the best of the officer's judgement, on the person who made the return, or who should have made one.