Due to the success of the series, CBS and their affiliates pressured Bell to lengthen the series from 30 minutes to a full hour. Bell attributed this change to the show's fall from number one in the Nielsen ratings, since the lengthening of the show led to the departure of a number of cast members. "The issue of performing in a one-hour show had not been part of their contracts," Bell said. This forced the show to recast multiple main characters and eventually phase out the original core families in favor of new ones. The show expanded to one hour on February 4, 1980. On June 6, 1981; it moved to 12:30pm Eastern, the slot occupied by "Search for Tomorrow" since its premiere in 1951, which ultimately led to the latter show moving to NBC. It airs 11:00am on most stations in the Central, Mountain and Pacific time zones, usually as a lead-in to the local noon news for most CBS stations outside the Eastern Time Zone (though some stations in the Central Time Zone opt to air it at 11:30am).