Complex sentence: Due to Canada's "simultaneous substitution" rules, WFFF frequently shifted its schedule to keep its commercials from being blocked in Montreal--however, whenever possible, CJNT duplicated the move in order to maintain the signal substitutions.
Split into simpler sentences: Due to Canada's "simultaneous substitution" rules, WFFF frequently shifted its schedule to keep its commercials from being blocked in Montreal. However, whenever possible, CJNT duplicated the move in order to maintain the signal substitutions.