On May 15, IOI's fan club published a document titled 'DC Inside IOI Gallery Joint Public Announcement' which clearly states their strong opposition to Jung Chae Yeon's return to DIA for as long as she remains active under IOI. 

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The announcement goes:

"Jung Chae Yeon (MBK, IOI)'s addition to DIA which was reported in the media this past May 10 is an act which undermines the decision of the public. Due to the decision [to add Jung Chae Yeon to DIA], the public sentiment toward the parties involved, including IOI, has worsened.

The current period, which is far from the official conclusion of IOI's one-year promotions, is not the right time [for Jung Chae Yeon] to join DIA. We cannot accept the agency's decision which we expect will have a negative effect on IOI's group activities as well as Jung Chae Yeon's promotions. 

We raise our voices against MBK Entertainment's irresponsible attitude in having no consideration toward its star's health, poor handling of schedules, and tarnishing of image. This is the fans' request which in no way is a reflection of Jung Chae Yeon's personal wishes. 

We oppose Jung Chae Yeon's addition to DIA while she is promoting with IOI, and should Jung Chae Yeon join DIA during this time period, we will boycott all [of DIA's] activities. We request an official apology from MBK's CEO and producer, and the promise to do everything it takes to let artists get plenty of rest and support so that Jung Chae Yeon will not be hindered in her activities."