(1) In this section 'employer's liability for the period of 12 months' means the aggregate of -
(a) all sums which an employer was liable under this Chapter and any regulations under this Chapter to deduct from emoluments to which this Chapter applies paid by the employer, and
(b) all sums that were not so deducted but which an employer was liable, in accordance with section 985A and any regulations under that section, to remit to the Collector-General in respect of notional payments made by the employer,
during the period of 12 months referred to in subsection (2), reduced by any amounts which the employer was liable under this Chapter and any regulations under this Chapter to repay during the same period, and subject to the addition of interest payable under section 991.
(2) There shall be included among the debts which under section 81 of the Bankruptcy Act, 1988, are to be paid in priority to all other debts in the distribution of the property of a bankrupt, arranging debtor o