The official Pokémon movie website has updated. Translations follow:
Media Information
Magazines:
Friday June 1st: "First Grader Magazine" - Announcement of the results of the drawing contest
Friday June 1st: "TV-kun" - Presentation of the new Pokémon, information on the pre-order ticket, etc.
Friday June 1st: "Kindergartener Magazine" - Presentation of the new Pokémon, etc.
*Note that these are the scheduled publication dates, and as such are subject to change without notice.
Source:
http://www.pokemon-movie.jp/news/?p=3309