Where an amount (in this section called the principal amount ) payable to the Registrar by an employer other than the Commonwealth under subsection 47(1) (including that subsection as varied under subsection 47(4)) remains unpaid after the time by which it is required to be paid:
(a) the principal amount continues to be payable by the employer to the Registrar; and
(b) the employer is liable to pay to the Registrar, by way of penalty:
(i) in a case where the employer is a government body--an amount at the rate of 20% per annum on so much of the principal amount as remains unpaid, computed from that time; and
(ii) in any other case:
(A) an amount (in this subparagraph called the relevant penalty amount ) equal to 20% of the principal amount; and
(B) an amount at the rate of 20% per annum on so much of the principal amount as remains unpaid and so much of the relevant penalty amount as remains unpaid, computed from that time.