It will darken like crazy, but, I do not believe it will burn. There are those that disagree.
To be more clear, the bark will get black, or near black at those temps, if there is a lot of sugar in the rub. But, I have never tasted bitter characteristics, that I would equate with burning. Some find the dark bark to be too difficult to get past.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
"perhaps...but then again...maybe not..."