I have a 7.5lb brisket im going to do overnight friday night.
Planning on 12-14 hours at a cabinet temp of 225*.
I really dont need the brisket till saturday night, so is there any reason to not cook at a lower temp to extend cook time, if even just a little bit?
too low and you can dry it out. 7 lbs is not that big to begin with, it may not take that long. I would be prepared to FTC for a few hours. You can always reheat in a covered foil pan with some beef broth. Brisket takes good reheated.
You should be fine at the 225º range. If I remember right WTS suggests 200º when he pulls his and puts it in the oven for the overnight. Make sure you Change the water bowl out and scrape around the drain hole in the V-tray before you got to sleep.
I smoke/cook mainly flats, choice cuts or certified Angus. I used to use a 200°F. As long as you don't expect to take them to an internal temperature beyond 185°F, it will not dry out the brisket.