【Sigmastar-KY】Announcement of the Promotion of Mr. Luo Zhihua, Senior Associate Director of the Company's Operations Department, to Vice General Manager

1. Type of personnel change (please enter spokesperson, acting spokesperson, important operational executive (e.g., CEO, COO, CMO, CSO, etc.), financial manager, accounting manager, corporate governance officer, information security officer, R&D manager, internal audit manager, or litigation/non-litigation agent): Vice General Manager of Operations Department 2. Date of change: 2026/05/13 3. Name, rank, and resume of former occupant: Luo Zhihua, Senior Associate Director of Operations Department 4. Name, rank, and resume of new occupant: Luo Zhihua, Vice General Manager of Operations Department 5. Type of change (please enter "resignation", "job adjustment", "redundancy", "retirement", "death", "new appointment", or "dismissal"): Job adjustment 6. Reason for change: Promotion 7. Effective date: 2026/05/13 8. Other matters that need to be specified: None.