I was watching the "Double Date" episode of three's company on a local station, and it was toward the end, so I expected that they would break in the middle of it, then come back and end the show after finishing the scene. Instead they went to break after Jack thanks Larry for helping him with his date (just like N@N), and they return with a different tag which shows Jack's date telling him she would take care of him while he's sick and then they show Janet and Chrissy in there night clothes coming out and ruining it for Jack and his date. This was instead of the scene with Janet and Chrissy catching Jack's cold. Was this an alternate tag, or just another scene that nick at nite doesn't show but local stations do?

It's just a scene N@N doesn't show and locals do.
The 'real' tag was shown by N@N when all 3 are on the couch in a blue cover.