Complex sentence: YTV and Treehouse, have also carried Nick programs for many years, under output agreements with Viacom, and they continue to do so, since they have near-universal coverage across Canada on basic analogue cable, whereas Nickelodeon is limited to digital distribution.
Split into simpler sentences: YTV and Treehouse TV, have also carried Nick programs for many years, under output agreements with Viacom. They continue to do so, since they have near-universal coverage across Canada on basic analogue cable, whereas Nickelodeon is limited to digital distribution.