I want to cook a 7 pd brisket flat tomorrow but it will be below zero tomorrow in Chicago. I thought I'd try it in the oven, sorry! The recipe I want to use has me cooking it uncovered for 1 hour at 350 then wrapped for 3 hrs at 300. BUT the recipe is based on a 4 pd flat not a 7 pd that I will be using. I know to probe it and I can use my Maverick. I'll start probing at 190 but how much longer do you think it will take if it's 7 pds? I want to try and time it for 5:00pm. Thanks for the help.