A couple of examples I remember from growing up near LAX on the Hollywood-Westchester system in its AT&T Broadband, Comcast, and Time Warner Cable days (now it’s a Charter Spectrum system):
Example 1
Channel 38 was shared by CSPAN2 and the then-Fox Sports West 2 (the then-cable home of the Los Angeles Dodgers, now known as Bally Sports SoCal). I don’t recall what time during the week that slot would switch from CSPAN2 to FSW2 or the other way around, but I seem to remember FSW2 occupying 38 all day on weekends; but if the Dodgers had a day game during the week, the channel slot would be switched to FSW2 regardless.
Both channels would get their own full-time channel numbers when Comcast conducted a January 2004 realignment of channels 2-99 putting all channels of the same genre (locals, sports, news, entertainment, etc.) together. FSW2 was moved to 61, just above the then-Fox Sports West (today’s Bally Sports West) on 60; CSPAN2 moved to 70, one click above the main CSPAN on 69.
Example 2
Channel 28 was shared by the Educational Access Channel (now UCTV) and the TV Guide Channel, back when it had the scrolling listings. By the time Time Warner Cable took over this system, these two channels would get their own full-time channel numbers, with the former staying on 28 and the latter moving to 29. Channel 29 would be removed when the scrolling listings were discontinued.
Anyone else here who lives (or lived) in or near that area is welcome to add more examples I may have forgotten.