Read this: The CBC's flagship newscast, The National, airs Sunday through Fridays at 10:00 p.m. EST and Saturdays at 6:00 p.m. EST. Until October 2006, CBC owned-and-operated stations aired a second broadcast of the program at 11:00 p.m.; this later broadcast included only the main news portion of the program, and excluded the analysis and documentary segment. This second airing was later replaced with other programming, and as of the 2012-13 television season, was replaced on CBC's major market stations by a half-hour late newscast. There is also a short news update, at most, on late Saturday evenings. During hockey season, this update is usually found during the first intermission of the second game of the doubleheader on Hockey Night in Canada.

During what television season did the CBC start broadcasting Hockey Night In Canada?
What is the answer? (If it cannot be answered, return "unanswerable")
unanswerable