Yellow Moon,
I can't answer your questions about the formatics of the show in particular, but I can maybe shed some light regarding WIZN's interest and placement of the show.
First, I guess this show is planted on Sunday mornings because that's when it's available live off the bird? That's my assumption anyway.
I'll also assume that this has been carefully thought out by the syndicator because that time slot is stereotypically the "throw-away" programming zone. Sunday mornings are a chance for a station to broaden its horizons in one aspect or another that it normally doesn't cover during the week in any form. Many choose PSA type programming to satisfy Public Service requirements. Others choose to carry syndicated shows that don't generally mesh with a popular-formatted station, which is what WIZN has done. Additionally, as WIZN is (currently) a rock station, as the blues was a base for rock, it's sort of like the station's time-warp to cover their historical roots.