The 3-2-1 method is specifically for those cooking at 225*. If you are cooking higher than that, then you have to cut back your times. I cook my St. Louis ribs at 275* and it takes about 4 hours total. I usually go 2 hours nekkid, pull them, wrap them and put them back on for the remainder of that next hour, pull them, go nekkid again, and put them back on for another 30 to 45 mins. So, if I start my ribs at noon, I pull them off at 2 pm. By the time I have wrapped them and get them back on, it is around 2:15 and I cook them wrapped until 3. Then I unwrap them and put them back on until they pass the bend test and a toothpick slides easily into the meat between the bones.