NIS America sent out the following
The release for RPG Maker MV will be delayed due to ongoing issues with development. Until they are resolved, the release date will be postponed for later in 2019. We apologize for the inconvenience caused to all those who are looking forward to this game, and we are taking action in order to deliver the best possible product to our fans. For more information regarding RPG Maker MV, please visit the official website. Thank you for your patience and understanding, and we look forward to meeting you with our next announcement.
A delay is unfortunate, but if it means the game is better, then its for the best