I've made several pork shoulders and briskets now, and I've noticed that about six hours into the smoking, I have to open up the bottom air grate and daisy wheel more and more to keep the same temperature. Yesterday I had the door half open and the cap off completely to keep around 250. On a lark, I decided to pull everything out (meat, grid, platesetter), and clean out the ash clogging the intake holes. Took about six minutes, but when done the heat came back up nicely and I was able to put the grate and daisy wheels to more reasonable settings.
Is this typical? I'm using lump but not BGE brand, and I know there are a lot of small pieces.