Update: I did find the proof John Boy and Billy played olides music for those stations that wanted it. The article was actually about the time they played "Another One Bites the Dust" immediately after the show reported on a sniper in Washington, D.C. It was unfortunate that I had to put this information in the Wikipedia article, but there are three justifications for doing this. One is that the article did offer proof that there was an oldies option (the country and oldies stations were not playing "Another One Bites the Dust"), and the other is that the headline of the article sort of gives away what happened, so it sort of requires an explanation if I'm going to use a source. And, finally, it illustrates the nature of the show's automation system: they didn't know ahead of time the song was going to play at this unfortunate time.
This was years ago; is Sunny using classic rock when they air the show?