Ah...that may explain the long cook, Hoss. I thought you were doing a Boston butt. You probably had a "picnic" cut (the higher part of the leg, which is actually a little tougher meat). Funny thing about pork butts....kind of unpredictable! I've cooked ones that have taken at least 1 1/2 hours per pound, and ones that took barely an hour per pound! You just can't see inside that piece of meat and look at the tenderness and fat!
In the future, if you start one early and it gets done before you're ready to eat, just leave it in the smoker after it hits 200 at a setting of 140. It will "rest" in the smoker until you're ready, but the cooking process will stop. I've done this many times with no adverse effects.