257   Apportionment in practice

(1)  A premium or an amount is to be apportioned in accordance with the Schedule of Apportionment adopted for the time being, except as provided by this section.

(2)  An insurer or an insured person may apply in writing to the Chief Commissioner to apportion a premium or an amount on a basis other than that provided by the Schedule of Apportionment. The Chief Commissioner may apportion the premium or amount on the other basis.

(3)  In particular, if the Chief Commissioner is not satisfied that a premium paid or another amount in relation to a contract of insurance has been properly apportioned for each risk insured, the Chief Commissioner may determine the apportionment, reassess the liability to duty and charge duty accordingly.