Yeah, I think this is nearly impossible. Plank is currently selling a large number of his shares in UA to diversify his portfolio or something like that.
I live in Baltimore and he recently purchased the water taxi system here, is opening up a brand new luxury hotel in fells point this winter and then has the multi billion dollar Port Covington project on the horizon. Everything he does is to further UA. The water taxis will allow employees to live in the more popular areas of the city (Canton, Fells Point, Fed Hill) and still be able to get to work easily and efficiently. The Hotel is where UA athletes (and others of course) will be staying while they are doing their promotional activities in Baltimore, it is directly across the river from the current HQ. He built UA up from a flower selling business to a behemoth that continues to grow, can't see him getting out now.