Complex sentence: In the fall of 1965, the show was switched to an earlier time slot of Sundays at 6:30pm, but the program had to share its time slot with other television programs on NBC, and was telecast every other week.
Split into simpler sentences: In the fall of 1965, the show was switched to an earlier time slot of Sundays at 6:30pm. That year, the program had to share its time slot with other television programs on NBC, and was telecast every other week.