Following 'Produce 101' season 2, Ha Sung Woon, originally a member of HOTSHOT, re-debuted in Wanna One. Another HOTSHOT member Noh Tae Hyun also recently re-debuted in the group JBJ. 

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At the showcase for JBJ's debut mini-album 'Fantasy' on October 18, Noh Tae Hyun talked about referring to Wanna One as 'sunbaes'. He commented, "I've recently met Ha Sung Woon. He said he saw our teaser and said it was cool." Noh Tae Hyun playfully added, "He also told me to call him sunbae from now on so I said I will."

The idol also expressed gratitude in being able to promote alongside Wanna One, as well as Rainz, saying, "We got to promote during the same time as Wanna One sunbaenim and Rainz sunbaenim, all who were on 'Produce 101' with us. I'm even grateful to hear that we're in a friendly rivalry."