I'm in the process of smoking a 7.5 pound Bostonian Butticus for dinner. I started it last evening around 6:00 or 6:30. Never once did the temp rise about 250 or drop below 200 from the time I started the fire until the time I went to bed at midnight, usually maintaining a 220 temp during waking hours. I awoke this AM to a chilly Egg. My dome temp fell from lofty heights to 160 degrees and my meat temp is 132. Nothing better than to wake up after a restful night to a cold Egg, having to rebuild the fire and take out that butt.
This has happened to me the last three times I've made a butt. It seems my Egg has been cursed. I intentionally started the cook earlier than needed because I've come to eggspect such unfortunalities, but it's still frustrating!