I did some research and found that the sites you most likely got them from are "unofficial" sources. Wikipedia and IMDB cannot be completely trusted. Wikipedia has the problem of being able to be edited by ANYONE. It is possible that someone who didn't have all the facts made those lists and didn't fully check their "sources". Heck, if you just look at the air dates provided you can tell it's not in order.
IMDB on the other hand seems to REFUSE to remove a certain title that will NEVER happen. (Yep, "The Great Growing Sky Stone" is still around, just moved to an episode.) Until they remove it, we can't trust it.
Then there's TV.com that has a 27th episode listed where Ozzy and Strut returned. Most likely, that information is from some fan who wants them to appear again. Sadly, we have to admit the fact that it NEVER happened. So yeah, that can't be trusted either.
We of The Gang of Five took great care in providing the order that the episodes aired in when it first came out. We have stuck by it since the start. It's been recorded by us fans, and it's the one that shall remain official unless Universal themselves say otherwise. So far, we have yet to get complaints about the order of the episodes. So it shall stick.