13(1) Where a person becomes liable for a penalty under paragraph 1, 1A or 2 HMRC shall–
(a)assess the penalty,
(b)notify the person, and
(c)state in the notice a tax period in respect of which the penalty is assessed (subject to sub-paragraph (1ZB)).
13(1ZA) Sub-paragraph (1ZB) applies where–
(a)a person is at any time liable for two or more penalties relating to PAYE returns, or for two or more penalties relating to CIS returns, or for two or more penalties relating to apprenticeship levy returns, and