Section 46A. Except as otherwise provided in section 180F, when any domestic company which has insured the payment of the compensation provided for by chapter one hundred and fifty-two becomes insolvent, or is unable to pay in full its liabilities as set forth in sections ten and twelve, unpaid losses under its workers’ compensation policies shall, in the distribution of its assets, whether liquidation is effected by a receiver or otherwise, be deemed and treated as preferred over all claims except debts due the United States and debts or taxes due the commonwealth or any city or town thereof.