According to page 8 of the latest issue of Star Wars Insider (#150), every short story in the magazine beginning with the first part of "Blade Squadron" in issue #149 is part of Lucasfilm's new unified canon.
Lightsaber Rattling was the first to spot the text bubble in issue #150, seen above, that clarified the stories' status. As The Hollywood Reporter points out, that makes "Blade Squadron, Part I" the first piece of literature published in the new canon.
5/10 - Jonathan Hales
5/12 - Domhnall Gleeson
5/13 - Milton Johns
5/14 - George Lucas
5/16 - Star Wars: Episode II Attack of the Clones (2002)
5/19 - Star Wars: Episode III Revenge of the Sith (2005)
5/19 - Star Wars: Episode I The Phantom Menace (1999)
5/19 - Peter Mayhew
5/19 - Claudia Karvan
5/21 - Star Wars: Episode V The Empire Strikes Back (1980)