Where, during the relevant year, it is found by an authority that any instrument of payment issued by it as payment of any relevant benefit F1... on or after 1st April 1988, but before the relevant year, has been returned to that authority without having been presented for payment or has passed its date of validity without having been presented for payment, the deduction referred to in article 13(1) shall be the amount of any subsidy that has been paid in respect of that instrument.