I've heard texas was thinking about making Mack the AD, so I doubt it. Now I could see texas announcing Mack will step down at the end of the year and start the process of finding a coach.
Brown could have moved to AD a few a years ago, had they orchestrated it well. The atmosphere in Texas now is that he's used up all of his good will. Scapegoating coordinators for years, blaming everyone but himself, hiding behind Joe Jamail and Dodds. People have had enough.
When Darrell Royal died, it started the process. Now that Dodds is leaving, Brown is fresh out of friends. He does still have a lot of big money backers, but if he keeps shitting the bed, I don't think he gets another season, much less the AD job.