I did two butts for a super bowl party (Go G-Men) last night. Put them own Saturday night around 8:30 pm. These were large butts, about 9 lbs each. Went to bed with the dome temp steady at 260. Woke up 7 hours later to find it had dropped to about 210 and I don't know how long it had been there. Got it back up to 250-275 where it needed to be but the butts were still in plateau at 3pm and I needed to have the pork pulled by kickoff ((5:30 pm CST).
So, I pulled them off and put them in my indoor convection oven at 375. Fortunately the higher temps forced them right through the plateau and they hit 195 at 4:30. Let it rest for 45 minutes and I had enough pulled for sandwiches just at kickoff. It was great too.
I think I lost a lot of cook time with the overnight fall in temp. This cook verified, however, that butts are one of the easiest things to cook because even when you screw it up, they still turn out great. Very forgiving.
VFL (Vol for Life)