Originally, the three-hour show aired Friday nights from 10:00 PM to 1:00 AM, but when the management at KPFK threatened to cancel the show, the producers were able to negotiate a schedule change. The last hour of the program, which was largely devoted to playing old-time radio shows, was eliminated, and beginning in May 1975, "Hour 25" aired on Saturday morning from midnight to 2:00 AM. In October, 1976, the show moved back to its original starting time, Fridays at 10:00 PM, and ended at midnight. It would then continue airing in this timeslot for the next two decades.