Although I usually cook packers, this should go for flats too. A brisket cooked to 160s, then foiled until 205 should still be sliceable. I usually don't foil, but when I do, I don't add any liquid. If you add liquid and foil too soon, it's like putting it in a crock pot and you may have to shred it. As for temperature, I start checking for probe tender when it reaches 195 and have never needed to go over 205.
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