The "Upstairs, Downstairs" debate!

[minor muppetz]

Which explains the announcer and the older CM puppet.

Actually it looks like Me, Claudias and Upstairs, Downstairs both used the same Cookie Monster puppet (I think they stopped using that puppet and built anew one in either season 13 or 14).

 

[minor muppetz]

I'm not sure if I'm wrong about whether the regular room changed in the 1990s or if it's just me, but if it was rebuilt, I assume it would be in season 25, when the show moved production to another studio.

Season 24 may be when the Sesame Street and Super-Grover openings changed, but that doesn't mean that the Monsterpeice Theater opening had to change then (I wonder when the Masterpiece Theater opening changed). The Sesame Street News title card changed many times (even if the logo was basically the same), and Here is Your Life had many different logos. And the Sesame Street opening has changed many times over the years, not just in season 24.