I received an email that from Aug thru Oct, if you charge $750 on your US Airway Barclay Master Card, you will get 15,000 miles. My wife didn’t get this offer, so I think it might be targeted, watch out your email and junk folder. J
If you’d like to get this kind of offers, I’d suggest you opt-in their email communication.
This card is churnable and you can get it every 3-4 months, first year is free, 40k miles sign-in bonus.