Until 1983 (some sources say 1984), 1983 was when I last remembered channel 50 being on the air. Channel 50 until 1983 was PBS station WCAE out of NW Indiana. Metrowest (now Newsweb) owned the channel 56 license, and in 1985 or 1986, Metrowest and the people who originally held the channel 50 license, hoping to get back on the air, swapped licenses, and the commercial allocation got moved to 50, because the station could be moved to Chicago, whereas then, 56 could not, due to channel 60 already being in Chicago, but also, to protect 1st adjacent 55 in Kenosha Wisconsin. C HG annel 50 wouldn't go back on the air until January 1987 as WPWR-TV. Not sure what was wrong with staying on 60. Had 50 gone back on the air as PBS and remained non-commercial, 56 would not have seen the light of the day., since at time, the channel wasn't able to be moved to Chicago. Today, under the channel repackaging, and their rf channel number being 17, 17 is no longer eligible to move to Chicago, in order to protect WBME-CD in Milwaukee, who's also on 17.