SAST says this was a LM-6A carrying Shiyan-27A through F: https://mp.weixin.qq.com/s/NvJYY2S-PoytsIOkFxrLog
For this mission, the Long March 6A rocket achieved its first multi-satellite side-mounted launch, with the central load-bearing cylinder adopting a composite material structure. Due to the narrow gaps between the satellites, the satellite integration process was highly challenging. Drawing extensively on the experience of other models, the team ensured an efficient and safe integration process through various methods, including digital model verification and satellite-rocket integration tests.Additionally, for this mission, the processing and rocket integration plant for the core stage and booster of this mission was different from the previous launches, posing an adaptation challenge for the rocket. Through repeated analysis, coordination, and verification, the Long March 6A launcher has proven fully capable of handling unloading and recovery operations at the new site. In future missions, the appropriate facilities can be selected based on actual requirements.
The Long March 6 modified rocket was developed by the Eighth Academy of China Aerospace Science and Technology Corporation. It is my country's first solid-liquid bundled medium-sized carrier rocket. The entire rocket is a two-and-a-half-stage configuration, and the carrying capacity of the 500-kilometer altitude sun-synchronous orbit is not less than 6.5 tons.The Shiyan 27 Satellites #01-06 were developed by the Fifth Academy of China Aerospace Science and Technology Corporation (CAST). The satellite is mainly used for space environment monitoring and related technical tests.
The satellites are individually named 冯阳、刘金鑫、王亚鹏、尚宇航 、王乐天、高洁 (Feng Yang, Liu Jinxin, Wang Yapeng, Shang Yuhang, Wang Letian, Gao Jie)https://weibo.com/5386897742/PnWdWrW9B
The April 19 launch of six classified Shiyan-27 satellites into Sun-synchronous orbit via a Long March 6A rocket has reinforced concerns over long-lived space debris. The mission’s upper stage was left in a 834 by 990 km orbit—where atmospheric drag is minimal and natural deorbiting could take over a century.While Shiyan-27 was a standalone mission, the use of rockets such as the Long March 6A and Long March 8 series for China’s two, 10,000-plus satellite megaconstellations could mean a proliferation of such debris, according to an analysis, which tracked the upper stages for most launches of the Guowang and Qianfan/Thousand sails constellations in similar altitudes.
