Like already stated, you can try. The folks at the Apple store have quite a bit of leeway in what they are allowed to do to keep customers happy. That said, I believe the "rules" state you have 10 days to return it. I returned my wifi-only model a week to the day and upgraded to one with the LTE radio in it and had no problems whatsoever.
Also, if it is jailbroken, make sure you restore the device back to a new iPad before taking it in there.
Apple states that you have 14 days to return an item for a full refund, 30 days for an iPhone. This applies to the online and retail stores. Here is Apple's official return policy.
Originally Posted by johnbergsing
Apple return policy is 14 days from date of purchase. No Apple retail store will make this kind of exception.
I think you have zero change of exchanging an iPad after 3 months. You're going to have to chaulk this one up to "live and learn". You can sell the iPad and use the money toward the next model.