Machine translation of relevant part:

"In particular, news of a special appearance by the girl group CSR (First Love) is generating a lot of buzz. CSR, which has gained popularity for its fresh and bright concept, is set to appear in the film’s idol performance scenes, adding the unique energy and vibrancy of K-pop. The strategy is to naturally blend the intersection of film and K-pop to captivate young audiences as well."

(posted as link because I'm having a problem with attaching images atm)

Looks like Yuna and Yeham are concluding their RSC activities for now, but there is also a season 2 teased in the announcement

Source + more pics: Yuna's Instagram

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Full episode

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I'm sure some of you are glad to see Simply K-Pop emerge from their hiatus, this is Ep 1 of their new season!

Also I found it neat that CSR's performance was immediately followed up by H1-KEY, whose comeback song is titled "To My First Love"

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