according to this, the safe trainees are:
c group: fyn, xingqiao, hsinwei, cai bing, ziyin, xiaoting, wen zhe, su ruiqi
k group: youngeun, myah, dayeon, bahiyyih, chaehyun, yujin, bora, yeseo
j group: mashiro, ruan, ririka, yurina, shana, may, manami, hikaru