I'm afraid that will not be able to tap out a credit if you have progressed to the next year. And you will lose. Because they did not have to cut prices to do.
I'm afraid TAP will no longer be able to issue a credit note, if the lapse until next year and it will not disadvantage because there has been a price reduction.
I'm afraid that will not be able to place your TAP debt reduction, if you have gone too far to go to next year, and you will lose because it has not been to reduce prices.