some non PBS stations (WJRT and WGTU) airing Sesame Street,
At the time because the nearest in-market PBS station to Flint, WUCM of Bay City (WDCQ), didn't come in very well, and neither did its alternate stations from elsewhere, WTVS Detroit and WKAR East Lansing. And of course, WFUM was not on the air yet. WJRT dropped Sesame sometime in the mid-1970s.
WGTU carried the show, as PBS service in Northern Michigan did not come until WCML Alpena opened in 1975. (It was the 1980s until Traverse City and Cadillac got PBS; in all cases, from repeaters of WCMU.)
and CKLW(CBET) has no airing of Sesame street.most people can assume that CBET didn't air Sesame Street until the Canadian version went into production.
Or even until CKLW became a full CBC O&O, as CBET, in 1975.