Coming from a GameSpot interview with Koji Igarashi and Shutaro Iida...
GS: How is development progressing? You recently had to delay the game to 2018. Have there been any unexpected hurdles in development or is it just taking a longer than you anticipated?
KI: Development is generally going smoothly, but there have been a lot of troubles. We encountered a lot of problems during development. Right now, we're trying to speed up the development more because we had to make the system first and then go from there and just created more and more content. It's quicker now in general.
GS: A lot of the later Castlevania games share many similarities with Metroid. What are your thoughts on the new Metroid game that was announced for 3DS?
KI: The two of us are extremely excited! [Laughs] We're looking forward to it!