I accidentally did something similar. I ordered an item, and paid for overnight shipping on a Thursday morning. The item didn't arrive as promised on Friday, in fact it didn't arrive until Wednesday the next week. That weekend, I called in complaining that I hadn't received my item. The label was printed Thursday, but UPS never picked up the package. They assumed it was lost and re-shipped my package. Low and behold, I received both packages and ended up with a 2 for 1. I kept the extra still in the box for a month, figuring I'd get a call from Amazon eventually asking for it back - when I never heard from them I decided to sell it.