The group released their previous Korean album, "Chained Up," nearly six months ago.
An age 19+ rated sexy version was also released along with the regular version.
Hyosung is returning as a soloist over 10 months after she released her last album.
Two audio teasers of tracks from the upcoming album were released through Red Velvet's official Instagram.
Image teasers of Yeri and Irene were released as it was also reported that the members have finished shooting their music video.
Girl's Day previously had a comeback in July 2015, nearly eight months ago.
According to insiders, the title track has already been selected.
The singer is expected to compete with a slew soloists from her former group, including Taeyeon, Tiffany, and Yuri.
The group has already finished filming their comeback music video hinting their return to the stage is sooner than expected.
The date was announced at the end of the most recent episode of K-pop Star.
Jessica's agency responded to the intial rumors that said Jessica is working on an album and preparing a comeback.
Taemin drops a highlight medley for his upcoming 'Press It' album.
The singer-actress mentioned that she would be working on music projects with the group for the next few months.