(1) In the application of this Act and the Levy Act in relation to a foreign - going ship in respect of a quarter, regard shall not be had to a time when the ship was in an Australian port during the period (if any) that, in accordance with subsection ( 2), is the exempt period in relation to the ship for the quarter.
(2) Where levy is payable in respect of a foreign - going ship for a quarter, the exempt period in relation to the ship for the next succeeding quarter is so much of that succeeding quarter as occurs before the expiration of a period of 3 months from the earliest time during the first - mentioned quarter when the ship was in an Australian port, other than a time by reference to which levy was not payable in respect of the ship for that quarter.