This episode is strange because the teaser was obviously filmed in 1958 very close to the pilot or the first few episodes. Donna's hair is noticeably darker and the kitchen looks different despite this being the last aired episode of Season 2. They must have saved it from an earlier episode to pad the running time on this one. Since it only featured Donna and Carl and not the kids, they probably figured they could get away with it.

If the front door has that stained glass, that's a dead giveaway...that was modified to regular glass. Also, that bottom of the stairs newel post extends up to the unseen ceiling, which they changed later.

The entrance doors to Alex's office were also changed, from old-fashoined mulit paneled doors, to louvered doors. All this was changed early in the 2nd season.