Don't think they're doing those. ADV released and prob has rights still. Aside from you're probably thinking of Hesei trilogy heh
All Gamera films after 1989 are in the Heisei category. As for the Heisei Trilogy, I'm not sure who has the rights to those right now.
Incidentally, the upcoming double-feature DVDs have two different dubs for two films:
Gamera Vs. Gyaos and
Gamera Vs. Guiron. Listen up, cuz' I'm about to school ya'!
TWO DUBS:
One is the AIP (American International Pictures) dubbing, done by Titra Studios (AKA: Titan Productions) in New York. They dubbed
Gamera Vs. Barugon (as
War of the Monsters),
Gamera Vs. Gyaos (as
Return of the Giant Monsters),
Gamera Vs. Viras (as
Destroy All Planets),
Gamera Vs. Guiron (as
Attack of the Monsters), and
Gamera Vs. Jiger (as
Gamera Vs. Monster X). This is the most preferable of the two by fans.
The other: The dubbing for
Barugon,
Gyaos, and
Gamera: Super Monster was Daiei's international print dubbed by Corporate Communications, Ltd. in Hong Kong (which dubbed countless Japanese and Chinese movies up to the early 80s). The dubbing for
Guiron was dubbed in Japan (by which company, I don't know). I don't know if
Viras or
Jiger had any international dubs, but it's possible.
In 1985, Sandy Frank acquired five movies:
Gamera,
Gamera Vs. Barugon,
Gamera Vs. Gyaos (as
Gaos),
Gamera Vs. Guiron, and
Gamera Vs. Zigra.
He only did his own original dubs for Gamera and Gamera Vs. Zigra (the latter never had an international print, because Daiei went bankrupt before they could commission one).
The upcoming DVD sets with have both dubs for
Gyaos (AIP & international), the AIP dub for
Viras, both dubs for
Guiron (AIP & international), and the AIP dub for
Jiger.
Zigra will do doubt have the Sandy Frank dub, and
Gamera: Super Monster will have the international dub (which was originally released to the US by Filmways).
So I hope this clears up any confusion!