Complex sentence: KSAZ dropped the CBS affiliation three days after the sale to New World became final, on September 12, leaving KSAZ temporarily as an independent station as Fox's affiliation agreement with its existing affiliate KNXV-TV did not run out until December 14.
Split into simpler sentences: KSAZ dropped the CBS affiliation three days after the sale to New World became final, on September 12. This switch temporarily left KSAZ as an independent station as Fox's affiliation agreement with its existing affiliate KNXV-TV did not run out until December 14.