Even though the stations swapped frequencies several times each day, the network affiliations remained constant: NBC network programming stayed on 820 kHz and ABC network programming stayed on 570 kHz.
On May 1, 1970, the unique dual split-frequency lives of WBAP and WFAA ended when WBAP paid $3.5 million to WFAA in exchange for sole occupancy of 820 kHz (and the NBC affiliation).