The artist isn't related to Disney/TOH, he's just really good at replicating the art style and is very dedicated to the fandom ^^
As far as I'm aware the only places where they are posted officially are Tumblr, Reddit, and Instagram (Some of the series are also posted with permission to AO3 as well). imo Tumblr is the easiest to sort by chronologically: https://moringmark.tumblr.com/tagged/the%20owl%20house/chrono
Unfortunately I don't think any of the platforms allow for bulk downloading of someone else's posts without some sort of 3rd party tool :(
It was, i'm sorry. It should be fixed now