CBS here (D/FW) had that problem with their broadcast on upper VHF and currently still broadcast on both that channel and a UHF channel. My attic antenna has no problem with either one but my rabbit-ear/loop antenna vastly prefers the UHF channel. My Zinwells and Artecs display both as virtual channel 11, one after another, but my Channel Master only displays one (which one I don't know, no frequency screen).
Aside: Some of my Zinwell ZAT-970As lose channel lock and don't snap out of it without a channel toggle when on the VHF stations. Really sucks when recording without monitoring.