The maverick.
Pretty hard to mess up a pork butt. I used to cook at 225. Now I just let the smoker settle in where it wants to. Usually around 300 degrees for a butt. Turns out just the same in less time.
I quit using mine. My 22.5 WSM does fine without it. Quit doing overnight cooks and went to Hot & Fast instead.
I used it all the time when I had a UDS. Worked great on that.
Thinking about just selling it.
I have never heard of smoking a frozen pork butt. I would think the center would not get cooked all the way or the outside would be overdone by the time the center was finished. Can you tell us more about using this method?
I start with all vents wide open, top & bottom. Once I get close to my target temp I close 2 bottom vent and adjust the 3rd bottom vent for temperature control. If I add a lot of cold meat I may open more bottom vents until the pit temperature recovers from the cold meat.