The date is September 18.
The Official website of KochiKame´s Manga ahs announced that the new Anime in celebration of it´s 40th Annoversary will be a 1-Hour special that will air in September 18.
The Story will be about Sabrina, princess of the Attakaino Kingdom, and someone who looks like Lemon Giboshi, either way she gets Kidnapped when she visits Japan, so Ryotsu will have to rescue her and show her they roll in Shimatachi!
Akira Shigeno (KochiKame) is directing the special at Studio Gallop; Takashi Yamada made the script for the special.
Via: Anime News Network