This seems to be a regular monthly event.  I normally don’t advise buying miles unless you need to top off an account for a redemption within the next year or so.  Here are the details of the promo in case anyone is interested.  I won’t be buying but if you need to top off your AA account, these US miles will become AA miles sometime next year when the programs merge.  These promos can be a good deal if you are not an American and don’t have access to credit card sign-ups.

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