For a long time, TBS was on Channel 17 on cable systems throughout most of the Los Angeles area as well, while WGN's channels placements varied; if some cable systems didn't carry WGN, they most likely offered WWOR instead. It used to be, at least in my area of Los Angeles, that TBS was part of the lifeline service along with the locals and public access channels; at least since the mid-90s, when TBS was gradually morphing into more a basic cable channel, WGN was used in lifeline instead.
Around 1995, the area cable system (when it was Continental Cablevision) re-shuffled the channel line-ups, with the locals being all grouped together, and premiums practically occupying channels 20-25, and the basics from 26 onward to 69. WGN moved from Channel 26 to 45 around that time, and later moved to its current channel 25 spot through another channel re-shuffling (by then, our service area was taken by AT&T Broadband, then later Comcast, and finally Time Warner). TBS moved from to 17 to 41, where it currently resides.