Before KGBS went full time, DXers got a treat on Sunday evenings as KGBS went back on the air at 9:00 PM Pacific, and stayed on until 2:00 AM Pacific. This coincided with KDKA's xmitter maintenance period Midnight-5:00 AM Eastern. (KDKA was the 1A station on the freq.) At 9 o'clock the DJ would do an ID and the FCC sign on legalities, welcome listeners to 50,000 watt KGBS-"Boomin' all the way up to Alaska!"
1020's mid day shift was 10 to 3 during that period, which I thought was unusual. I'm not sure if any other major station in the market was doing that at that time...Yes. They ditched Country in March, 1969, telling Billboard that they intended to put themselves "in between" KHJ and KMPC. We didn't have the term "adult contemporary" yet.
A few airchecks survive, and while the jocks (Bob Hudson in mornings, Bill Ballance in middays, Dick Lyons afternoons, Roger Christian and Bobby Dale late nights) were looser than KHJ and KRLA, the music was all stuff you'd hear on Top 40, up to and including Led Zeppelin.
This was the format that they had when Ballance started doing "Feminine Forum" in '71. Somewhere in '70, Ron Landry took afternoons and then in '71, they paired him with Hudson in mornings. They never really softened the music much, and so, I'd agree with Tomas that they were actually a Top 40. That lasted until '74, when they tried talk for a year, and then went back to Country until the December 26, 1976 launch of KTNQ.