Did a couple pork butts last weekend on my UDS. The things took a long time (about 17 hours at 225 deg). They seemed to hit a second plateau at 180 deg. I went to move one and I could tell it was too done; way too loose. I ended up pulling them off the smoker and they were overcooked and and mushy. What happened? I think I trust my thermometers. I usually cook to 195.