Official announcement of the DVD postponement is shown here on the sale information page where the date is changed to "postponed".
Official announcement, unfortunately, of the cancellation of Uchi's talk event related to the release of the DVD is here.
PLAYZONE 2007 Change2Chance stars Shounentai, Akasaka Akira, and members of Johnny's Jr. (including Uchi Hiroki). Its run on the stage finished in September, and the DVD was to be released in early November.
Thanks to musikologie for helping me track down a couple of links. I will post updates if there are any, as well as additional information.