“The area being shaped is consistent with the 180-foot width of China’s existing South China Sea runways at Fiery Cross, Subi, and Mischief Reef in the Spratlys and Woody Island in the Paracels. The work is taking place along the reef’s northwestern edge, the only straightaway available at Antelope to accommodate a 10,000-feet runway like those at China’s other outposts. The area being worked on currently extends 4,300 feet but is clearly a work-in-progress.”
“Other earth-moving in the north seems to anticipate the extension of the runway up the full length of this edge. Digging is underway for the foundation of at least one structure adjacent to the expected runway which matches the dimensions (200×200 feet) of the larger hangars located at China’s other South China Sea airstrips.”
“Though this preparatory work is the first sign of major infrastructure construction on Antelope, the reef itself has come a long way since AMTI’s last check-in. The landfill and dredging work at Antelope appears to be complete, with no dredgers in sight in recent imagery, and the finalized landmass now measures 1,458 acres…”
https://amti.csis.org/is-a-new-chinese-runway-taking-flight-at-antelope-reef/