8 hour Brisket

So I did my first brisket on the egg, an 8 pounder. I started it at midnight last night thinking 1.5 hours per pound, maybe a little more at 250 Dome temp, 225 grid temp. when I went to bed at 1:30am it was already reading 145, I was thinking this was the plateau and that it would stall for a long awhile. At 2:30am my remote temp gauge started beeping saying it was at 190? I ignored it and checked back at 5:30am. Dome temp was down to 150 and Brisket was at 146. I opened the vents and got it going again at 250 dome, back to bed. An hour and fifteen later when I checked it was at 195, dome temp 350. Turned it back down to 225 and 30 minutes later pulled it at 205, that was 8:30am. I triple wrapped it in foil and wrapped it in a towel. Since we are not eating until 3pm I am keeping it warm in the oven at 170 turning the oven off and on once an hour. I think it should be ok but I am confused about the fast cook time, anyone have any input about my cook or how long the brisket can wait in the foil? I will let you know how it turns out.