IGST refund regularization allowed where IGST and cess are later paid with interest and the Bill of Entry reassessed. Where inputs were initially imported under customs exemption without payment of IGST and compensation cess but the importer subsequently pays IGST and compensation cess with interest and secures reassessment of the Bill of Entry by jurisdictional customs authorities, the IGST refunded on exports will not be regarded as contravening the refund bar; the Explanation clarifies that benefit of the exemption is not deemed availed if IGST and cess are paid and only basic customs duty exemption remains.