Previously, it was reported that both IOI and DIA were scheduled to perform at the upcoming event. This led to a controversial question regarding if Jung Chae Yeon will perform as IOI, DIA or both. 

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On May 31, MBK Entertainment clarified, "Jung Chae Yeon will only perform as an IOI member at the 'Dream Concert'. DIA will not be performing. After a discussion, the members decided not to perform at 'Dream Concert', considering the difficulties Jung Chae Yeon will face [in performing with 2 groups]."

The label added, "Other DIA members are still focusing on comeback preparations. Seunghee departed the group, and now Jung Chae Yeon, Ki Hee Hyun, and maknae Chaewon have joined. The new team, now 7 members, are planning to present a new album as soon as possible."