Transfer of control of KMXB from American Radio Systems to CBS was filed and accepted in November of 1997, IIRC ARS had an LMA on the frequency which started around 1996. At that time, they were "94 Jamz"
American Radio got wind of an impending format change across town at Regent's Young Country 93.1 FM-- When they moved into new facilities in the old bank building on Desert Inn Road a music library was in place to launch "Mix 93.1"
ARS beat them to the punch, and 93.1 became oldies instead.