I have a 2x2 KALLAX and where I've just moved to I want to add some bigger KALLAX units. With the new units in place I wouldn't really have a place for my 2x2 so I'm curious about the buy-back process. I want to see what it would get valued at but I don't know when I'll actually get around to going to IKEA so I'm wondering if I were to submit an application and it was approved, do I have to bring the item in a certain number of days? Does it expire after a few months? Does it just sit on my IKEA Family account until I bring it in?