Dr. Phibes

There's a box set I want to pick up at Best Buy this week (Zombie Collection, if anyone is curious). The set is on order right now according to the site, and the store by my house isn't showing up as having it in stock for in-store pickup (even though I know they have a copy). My question is if I use my Best Buy bucks towards purchasing that set, and it takes forever to get a set in stock, will I end up losing my BB Bucks if I decide to cancel the order? I'm sure they'll get it soon, but I don't want to have it on order for more than a month.

Or does anyone know if the stores will have the 20% off box set sale?