So what's up with PSO2: The Animation?

Something that has been bugging me since the release of the game has been....If Episode Oracle is a retelling of Episodes 1 to 3, then what was up with "The Animation"? Was that a weird non-cannon "What if the world of PSO2 was an alternate one"? it's been bugging me since I started playing through the Story Missions...

It is completely canon, and acts as a a prelude to Episode 4 to a degree, taking place in the time gap between the end of Episode 3 and the beginning of Episode 4.

While it is canon, it is not required watching since most of the important plot points of it are explained in game. The only other real impact is for understanding a couple of cameos that happen in Episodes 4, 5, and 6.