I have Harmon XXV. Had it since 2018 and we are burning about 3.5 tons. I have 2 Tons leftover from last year. Should I rotate them? I was going to ask gun to move them out before new ones if it's necessary. They are out of weather in Bay of Building. No Animals have got into the bags that I can tell. Worth Rotating? I can't imagine pellets going bad unless some mice or such chewed into bags for fun.