When I have a packer and a big enough grate size I separate when the point reaches about 150-155*...gives slower cooking with better chances for natural moisture retention in the meat, along with self-basting with the fat-cap. Finish the flat however you like once separated (foil, or don't), but rest the point for 20-30 minutes on a board and commence cubing it up, toss in sauce in a bowl and return to open grates until the sauce caramelizes and browns nicely (about 2.5hrs @ 225*). They have a moist, tender chew with a light pop, complimented by a nice crispy exterior...great texture variances. Everyone has their personal preferences as to how they like their BEs, but everyone around here loves 'em this way. Once I learned this method, I quickly learned not to change it by comments from those who dined on them. BTW, I rarely use sauce when cooking my BBQ meats...this is one of the few times that I do.
If you make your burnt ends with too high of internal temp in the point before cubing it up the meat can become dried-out from overcooking. Some finish BEs in a pan dowsed in sauce after taking the point to a higher temp before cubing...just not my thing...seems so wrong to me, but, everyone has their preferences.
Eric
