I made a booking, paid it, and then realized I booked the wrong date. This was all done on the JAL Japan website paid with my Amex.

I immediately called them and they said would refund me once they received the money. I guess it takes a day for the transaction to post to my account.

So how long does this process take? The ticket I bought was an one-way ticket, so it's full fare and fully refundable.