Which country was that MacFon ?
Its 14 days in the USA as shown on Apples site for the iPad and 30 days for the iPhone
http://www.apple.com/legal/sales_policies/retail_us.html
USA...It must be up the the store as how lenient they will be. When I heard about the upgrade I thought for sure I was out of luck with returning. After sleeping on it, I headed to the Apple Store the next morning first thing. I walked through the door just as another guy did, both with our Apple bags in your hands. He was the first return on the day.