Worlds fastest brisket cook?

HellrodKC

Picked up a prime brisket from Costco yesterday afternoon. 14.9 pounds in the cryovac, didn't weigh it after trimming but there was a pretty good amount of fat removed. 

Fired up the egg at 11pm last night, had the temp settled in at ~260. Brisket went on at midnight. 

This is was my first time using my new fireboard thermometer, so got a probe in there, shut the dome and hung out for about 30 minutes just to make sure nothing went awry, and go to bed. 

Woke up this morning at 5:30 to let the dog out, and the fireboard app is already showing the brisket at 200. Some thermostat at this point had crept up to about 300. Grabbed my thermopen and confirmed the temp, and its probing really easily, so to me it's done. 

WTF happened here? My dome thermometer could be way off, but what else? Could this really just be that short of a cook? Has anyone ever seen such a smooth temp chart, almost zero stall?

im just glad I had the fireboard and checked it, saved me from throwing out 15lbs of prime beef! 

HellrodKC

Also, this thing is now FTCing until dinner, which is planned for 7pm tonight. I don't expect it to be warm still, how would you all recommend reheating?

ryantt

set the oven as low as it will go (ours is 155) and let it ride in there.  I did this last fall @cazzy recommendation and it worked like a champ.  I held about 9hrs.  

lousubcap

Check the calibration of your dome thermo, but if it ran for a great majority of the night at 300*F it is fast but not totally unreasonable.  Good that you checked for the "feels like buttah" in several places in the flat on the off chance that your probe was in a fat pocket.  And with the high cook temp many will cruise right thru the stall.  
Good plan with the use of the clock-box to hold.  

ryantt

One other quick thing make sure you let the steam off before you wrap it up to hold.  This will prevent the over cooked  carryover effect 

buzd504

Prime briskets can cook very quickly.