In Taiwan, Castlevania Advance Collection has been rated for the Nintendo Switch. This indicates that a release or announcement is imminent.
Castlevania Advance Collection was originally rated in Australia, although no platforms were specified. This time, though, things are different because we now know that the game has been rated on the Nintendo Switch as well as the PC, PS4, and Xbox One.
Based on the name alone, Castlevania Advance Collection may be a collection of Castlevania games released for the Nintendo Gameboy Advance.
On the Nintendo Gameboy Advance, three Castlevania games were published. Castlevania: Aria of Sorrow, Harmony of Dissonance, and Circle of the Moon are among them. All three received critical praise and are considered among the finest games in the franchise.
Source (via Gematsu, Game Ratings Taiwan)