So Nyeo Shi Dae is known to be resting from her throat illness and her return as MC on MBC Music Core will be postponed for a week.
An official revealed on 17th June, 「The condition of Tiffany's throat is still not good. We are thinking for her to rest for one more week and she will not be returning as MC on Music Core on 19th June.」
With that, it seems that chances are high that Yuri will return as MC on the show before Tiffany. Tiffany has been suffering due to vocal cord nodules and had been receiving treatment for it, but recently the symptoms are back again.
Meanwhile, as fixed MCs on the show, Yuri and Tiffany had left their MC-ing role on Music Core for about 3 weeks. And in these 3 weeks, special one-day MCs had stood in on the show.