Home Events Jason Isbell & The 400 Unit Honors Gregg Allman In North Carolina Jason Isbell & The 400 Unit Honors Gregg Allman In North Carolina planetsixstring June 19, 2017 comments off Tweet on Twitter Share on Facebook Google+ Pinterest Jason Isbell kicked off their lengthy summer tour by honoring the late Gregg Allman with a must-hear cover of “Whipping Post.”