Be careful to avoid having the water heater blanket touch the sides of the WSM. I still have melted insulation on the outside of my 22. Switched to the Guru WSM silicone cover for all my cooks regardless of outside temp. It helps me avoid reloading even starting at 7 pm for a normal 1 pm turn-in for pork.
Starting at 3:30 am for brisket works in hot/fast cooking. Is that what you are doing? Are you cooking flats or packers? I'm doing a practice tonight also but mybrisket and butts are going on at 10 pm.