Complex sentence: Until October 2008, WKCF was the only Hearst-Argyle owned station whose web site was not powered by Internet Broadcasting; that changed when Hearst-Argyle and Internet Broadcasting created a separate page within WESH's web site for the station.
Split into simpler sentences: Until October 2008, WKCF was the only Hearst-Argyle owned station whose web site was not powered by Internet Broadcasting. That changed when Hearst-Argyle and Internet Broadcasting created a separate page within WESH's web site for the station.