A short story for the new guys (and maybe some old timers, as well). You can use time, and you can use temperature, and you can use weather, and you can adjust your heat source - but the bottom line is - the meat is done when it's done.
I have made pastrami many, many times and the time on the pit has always been between 4 -7 hours (with the size briskets I buy).
Yesterday I went to smoke a pastrami that had been curing and I am glad we weren't counting on it for dinner last night (I always smoke it then let it sit for a day wrapped in the fridge and then slice the next day). Yesterday, after 9 hours on the heat the brisket was still almost 15 degrees form where I needed it to be so I figured it must be in a second stall and so I wrapped it in foil and put it back on the pit. That did the trick. The IT started moving up almost immediately and 1 1/2 hours later I was were I wanted to be.
The moral is - it may have always only taken 4 - 7 hours in the past but that doesn't mean it won't take 11 hours today!
The meat is done when it is done..............