Internal temps are a nice guide. As mentioned I would get the meat to be tender whether that internal temp on the flat is 202 or 205, it can vary. Around there it tends to be getting close. I like to rest my brisket 2 hours if i can in a cooler and open the cooler a couple times to not overcook it "when using a smoker." In your case just lower you oven temp as low as it will go or shut it off depending how low it goes.