Seoul: Retail giant Lotte Group announced the replacement of 21 CEOs across its affiliates and subsidiaries Thursday in a sweeping leadership reshuffle that comes amid growing concerns over a potential liquidity crisis. Shin Yoo-yeol, Lotte Group Chairman Shin Dong-bin's son and heir apparent, was promoted to vice chairman, assuming a full management role, according to the company. According to Yonhap News Agency, as part of the overhaul, 22 percent of executives stepped down, reducing top-level positions by 13 percent. The group said these changes aim to streamline decision-making and improve organizational efficiency. The reshuffle comes amid widespread rumors that South Korea's sixth-largest business group by assets is grappling with a liquidity crunch, driven by poor performance in its chemical and retail subsidiaries. To reassure investors of its financial stability, Lotte Group recently announced plans to use its flagship skyscraper, the 6 trillion-won (US$4.31 billion) Lotte World Tower, as collatera l for corporate bonds issued by Lotte Chemical Corp.