Shouldn't be an issue. I will typically load mine at the beginning of BP season in GA, and hunt with it for the rest of the season. Obviously, I'll re-load if I shoot at something.... I won't rely on a load if I've been out hunting and it was raining or really damp; I'll typically either shoot it or unload it by removing the breach plug because I don't want to take the chance on soggy pellets. But, if it's dry, I'll leave it loaded for weeks at a time.

I, too, unintentionally left mine loaded from one season to the next with no ill effects. We were supposed to get down to the lease and do more hunting, but one thing led to anothe and we never got down. Finally, the next season, I pulled the old smoke pole out and realized it was still loaded from the previous season. After unloading and a little bit of light cleaning (just to be safe and sure), it shot just fine.