The official Pokémon movie website has updated. Translations follow:
Wednesday June 26th: "TV Tokyo Music Festival" on TV Tokyo - Theme song performance (Sachiko Kobayashi and Shoko Nakagawa)
*Note that these are the scheduled publication dates/air dates, and as such are subject to change without notice.
*Broadcast dates will vary depending on where you live. (some areas exempt)
For details, please see the website of your local TV station.