Do you have official proof that the episodes aren't in the order of the original broadcast ?

Yes, according to Wikipedia and listing on Disney+ https://en.wikipedia.org/wiki/List_of_The_Avengers:_Earth%27s_Mightiest_Heroes_episodes#Season_1_(2010%E2%80%9311) https://www.disneyplus.com/en-gb/series/the-avengers-earths-mightiest-heroes/746QUhXvkYXm

Wikipedia and Disney+ aren't proof of the order used for the original broadcast.

The original broadcast was done by DisneyXD.

Even IMDB listed it as Wikipedia and Disney+. "Iron Man is Born" is the first episode, and it also serves as a pilot, which aired on September 22nd, 2010, then "Thor the Mighty" is the second episode, which aired on October 24th, 2010, and so on. DisneyXD isn't around anymore, all of it's shows are a part of Disney+ now

Did you read the Wikipedia page you are talking about ?

I quote : "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."

The September 22, 2010 date listed for the "Iron Man is Born" episode was an online preview which didn't count as we only take in account the TV broadcast date.

Sorry, my bad, but, do you mind changing the name from "Breakout (1)" to "Breakout: Part 1" as it's the correct name for it and more accurate? Or you can unlock it and I'll do it myself.

Did you read our rule about multi-part episodes ?