I invite you to read this previous content report.

The episodes weren't originally broadcasted in the correct story order.

If you check the wikipedia link that's mentioned there, it says "The series was broadcast around the world and released on DVD in the correct chronological story order (production order)." and the order I reference here is from that same article. So it would appear that there was a revision in what was said. Also the linked post says that the first line of the wikipedia article is "The first season premiered on October 20, 2010 with the two-part episode "Breakout", continuing on from the events of the online micro-series. This move meant that the series did not air on television in chronological story order; the broadcast of "Breakout" was followed by the episodes "Iron Man is Born", "Thor the Mighty", "Hulk Versus the World", "Meet Captain America", and "The Man in the Ant Hill", each one a compilation of four micro-series episodes, which all take place before "Breakout". The series took a hiatus after "The Kang Dynasty" and returned on May 15, 2011 in the United States." However, that same line now reads "The first season premiered on September 22, 2010 with the episode "Iron Man is Born". The series took a hiatus after "The Kang Dynasty" and returned on May 15, 2011 in the United States." It would seem that there was some revision. I'll look for a primary source, however.

This resource (https://toonxdba.fandom.com/wiki/September_22,_2010) says that on 22 September 2010 on Disney XD "Iron Man is Born" premiered and they use this (http://www.thefutoncritic.com/listings/2010/09/22/) as a reference and this resource (https://web.archive.org/web/20160409210646/http://tvbythenumbers.zap2it.com/2010/09/20/the-avengers-earths-mightiest-heroes-premieres-wednesday-october-20-on-disney-xd/) also says that Iron Man is Born will be premiering on 22 September 2010.

Here, we have the complete official press release from Disney XD on September 20, 2010, that was the source for the Zap2It article that you just link above.

It explains first that micro-series episodes (previews) will be broadcasted starting from September 22 and that the series itself will start on October 20 with the 2 episodes "Breakout".

Consequently, our listing is correct.

" The Avengers: Earth's Mightiest Heroes!, a New Marvel Animated Series, Premieres Wednesday, October 20 on Disney Xd Plus: micro-episodes introducing the team's core members will premiere Wednesday, September 22 at 8:30/7:30c. [...] The complete multiplatform rollout is: Wednesday, September 22

Disney XD will air a special sneak peek of the first micro-series episode, "Iron Man is Born!," at 8:30 p.m., ET/PT directly following premiere of the network's newest series, "Pair of Kings." "

Maybe we're interpreting this differently. I read this as "Iron Man is Born!" (and the subsequent solo episodes) as being the "micro-episodes" which introduce the team's core members. And these episodes began being aired from Wednesday, 22 September until the release of the first episode. If anything, the solo episodes should then be listed as specials.

Nevertheless, even if we do accept that the recognised premiere episodes Breakout parts 1 and 2 were released on October 20th (which I do agree is true), the press release doesn't even mention the 24th of October and that's when the database lists "Iron Man is Born!" as being released. I suppose I want to know the source for the episodes after the premiere being listed as being released on the 24th of October which I have not found, even the source you provided says that the micro-series episodes rolled out from 11th of October to the 15th October "with 4 micro-episodes stacked each night".

What I think happened is that the "micro-episodes" are the the full episodes "Iron Man is Born!", "Thor the Mighty", "Hulk vs the World", "Meet Captain America" and "The Man in the Ant Hill" divided into 4 parts each (for a total of 20 micro-episodes and forming a so called "micro-series"). So even if only the first "part" of the episode was released on 22nd of September, the mico-series is said to have been available on Disney XD on Demand at latest on the 15th of October which is still before the premiere of the Breakout episodes.

Taking in account that Disney XD explicitely indicate that the series premieres on October 20, the micro-episodes aired before that date are considered by TMDB as previews which we don't support. The king for us is the press release of the original broadcaster

Even if "Iron Man is Born!" is the title of one of the micro-episode, this is also the title of the complete episode that was broadcasted on October 24, as visible on this list.

Yes, but the press release does say that between 11 October and 15 October 2010 the "micro-series" was released on Disney XD on Demand. Is it a rule that the TV premiere of a show takes precedent to a digital premiere. Because it is my under standing that the list seems to be tracking TV specifically. Is it possible that they are not considering the digital release of the full micro-series, which I reiterate, is mentioned in the press release.

I mean, the "previews" don't have to be considered. But it seems to make most sense to me to either consider the "micro-series" as specials entirely or to change the chronology to reflect (as the press release states) its premiere sometime between 11 October and 15 October. This is if, of course, TMDB doesn't consider the TV premiere to take precedent.

@cortexcoil said:

Is it a rule that the TV premiere of a show takes precedent to a digital premiere.

Yes, we follow the TV broadcast and don't take in account the digital previews.

Noted. As a final statement I want to point out that on even on the broadcast list the supposed "premieres" are marked with (R) which I take to mean that it's a rebroadcast. It does seem clear in the viewing experience, from the press release and the production codes that there are 5 episodes that were intended to be watched before as a build up to the full premiere. While we don't need to consider the "micro-episodes" as episodes on their own, I argue that when they were released to Disney XD on Demand, that was their original premiere. At the very least, if they are causing a lot of confusion, they should be marked as a set of special episodes apart from the main series.