Jackie - don't think they're headlining those shows...Brett is bringing them out for this tour.  I suspect...much like ages ago when they played w/Kaki King @ SC, they flipped the bill in places where GPN would have "home field advantage."  Makes sense, otherwise things may fall flat for Brett's sets.  Although, I would assume, they're still technically the opener even for these shows.  

Brett's great IMO, but not everyone's taste.  Not really anything like GPN...much mellower.  I like his writing and soul.