Conclusive determination of tax liability precludes reopening after payment under the dispute resolution scheme in covered proceedings The designated authority must determine by order the amount payable on a declaration and grant a certificate stating the tax arrear and amount payable; the declarant must pay the determined amount within the prescribed period and intimate payment details to the authority, which will then pass an order recording payment. Every order determining the amount payable is conclusive on the matters stated and bars reopening of those matters in any proceeding under income-tax law, other law, or international agreements.