Red Sky (600227.SH) subsidiary Tongzi Chemical's production unit has completed maintenance and resumed production.

Zhtng Cijng APP News, Chtin Hu (600227.SH) released an announcement that its wholly-owned subsidiary, Guzhu Chtin Hu Tngz Huxu Yuxin Gngs (referred to as "Tngz Huxu"), according to the annual work plan arrangement, began planned maintenance of the production facilities on August 20, 2025, with an estimated maintenance period of 35 days. On September 26, 2025, the company received a notification from Tngz Huxu that the production facilities had completed maintenance and resumed production on September 25, 2025, with current production running normally.