Formally, depends on the sausage. Chicken sausages are pre-cooked, so as long as they stay cold and well-covered, they're good as long as leftovers would be. (Which is way longer than everybody thinks.) Curing and smoking are preservative methods, which can be taken as the equivalent of cooking for time purposes. (Moreso; you wouldn't hang up a cooked ham hock in the pantry for months at a time, but you would do for a cured one.)

Of course, the real trick will be cooking the everliving shit out of them if you're not sure. The Everliving Shit method is what I use for anything that might appear to be iffy! For sausages, that means splitting thm down the middle, or cutting thm into coins, to make sure they change color all the way through.