Yes. You can use the Discover it® Miles credit card to earn or redeem miles for Japan Airlines flights. There are no blackout dates. You simply use the Miles card to buy any Japan Airlines ticket and then, when you see the purchase on your Discover account, you can apply your miles to the transaction and see it credited to your account. The redemption ratio is 1 mile = 1 penny. You can combine miles and cash when redeem for airfare. It is much easier to redeem Discover Miles than Japan Airlines miles. JAL imposes a lot of restrictions and limitations on to reward flights. Plus, you have to pay taxes and fees from your pocket as they are not covered with miles.
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