I started a 8 lb pork shoulder at 10 last night.. I thought I had the temp stable at 250, but after checking it at midnight before laying down, it was up to 275.. I was worried it would keep climbing, so I closed the daisy wheels halfway.. I wake up this morning and its internal temp is at 165, but the dome temp was down to 200, and the pork shoulder bark has several areas of greenish gray tint on it.. Is this something to be concerned about? Anyone else seen this before?