How long do Console bundles usually last?

I have been eyeing a Wii U ever since the price cut. I kept checking to see if they were going to lower the 8 GB version as that is all I need, but they didn't. Then, I saw something very important: there is a Windwaker HD bundle with a special Gamepad design (not important, but cool) for the price of a standard Wii U Deluxe (why you wouldn't buy this is beyond me if you already getting one). I want to get this, but I need to know how long this typically last. It is called "limited edition" (obviously). Is that 1 month, 6 months, a year? Evidence from prior bundles from nintendo and others is prefferable. This is saving me $50, so I don't want to miss out.