A ship while being moved within a harbour which forms part of a pilotage district shall be deemed to be being navigated in a pilotage district, except so far as may be provided by byelaw in the case of ships being so moved for the purpose of changing from one mooring to another mooring or of being taken into or out of any dock: and a byelaw shall in every case be made for the purpose aforesaid in any pilotage district where any class of persons other than licensed pilots were in practice employed on 7th March 1913 (the date of the passing of the M1Pilotage Act 1913) for the purpose of changing the moorings of ships or of taking ships into or out of dock.

Until such day as the Secretary of State may by order appoint, subsection (1) above shall have effect as if for the words " being navigated" there were substituted the words " a ship navigating " ; and different days may be appointed under this subsection for different purposes.