7-15 minutes is standard for bromated high gluten flours in a. 60qt, but most important is at what hydration. You could mix for 10 minutes up to 20 minutes with non bromated flour to try to match the bromated. There are many factors though..it depends on where you are for hydration, when you ball the dough, how much salt, how much oil, how you ball, cold ferment or room temp ferment and how long etc etc. If your not seeing as much puff with non bromated with all else the same there are lots of things to get you more, mixing longer is one of them.
Most of the time I see non matching of hydration as the reason why people prefer one flour over the other. One brand of flour with the same protein content as another brand can sometimes require 5 points different to be a true hydration match. If hydration isn't properly matched you would need to do a much longer mix to get to the same amount of strength built into the doughs that feel wetter.