31(1)A penalty must be paid—U.K.
(a)before the end of the period of 30 days beginning with the date on which the notification under paragraph 29(1)(b) was issued, or
(b)if a notice of appeal is given, before the end of 30 days beginning with the day on which the appeal is determined or withdrawn.
(2)A penalty may be enforced as if it were corporation tax charged in an assessment and due and payable.