I'm almost positive that an unopened bag of Timberwolf is good for a year but you might want to double check with the manufacturer just to be sure.
BTW, I've noticed that on the store locator on their website NY has been added and removed numerous times over the years. I have no idea why this is but I can get Timberwolf locally at a several different locations, its been available here for years even though NY is not always listed on their store locator.
In addition, I only pay $25.99 for a 16.5 lb bag which is actually cheaper than buying it through their website. I found this odd too.