'Idol School' released the first preview clip on June 28. Viewers noticed that several trainees from the past JYPE debut competition program 'Sixteen' are participating in the new show.
On June 29, producers of 'Idol School' confirmed, "Natty, Eunseo, and Jiwon do not have labels at the moment. They're appearing on 'Idol School' as non-celebrities."
The first episode of 'Idol School' is airing on July 13.