I.O.I was initially planned to return in October 2019, excluding Jeon Somi and Yoo Yeonjung, but it was postponed to December. The comeback was eventually canceled in October due to scheduling conflicts between the members and the investigation of Mnet s vote manipulation.
However, according to Kim Chungha, one of the former I.O.I members, this year is the year they promised that they would come back as a group.
While Kim Sejeong was still part of I.O.I, she debuted as a member of Jellyfish Entertainment s girl group called gugudan in June 2016, together with fellow I.O.I member and labelmate Kang Mina. Once again, Kim was one of the main vocalists of the female act.