https://bsky.app/profile/planet4589.bsky.social/post/3lvcjbs3nwc25
LAUNCH at 1835 UTC Jul 31 of Starlink Group 13-4 from Vandenberg. 19 Starlinks aboard; speculation (but no definite evidence yet) that the launch may also have carried some NRO Starshields
https://bsky.app/profile/planet4589.bsky.social/post/3lve55tdm4s2u
Two catalog numbers extra in the gap between 2025-164A (PRSC-S1) and 2025-166A (Endeavour), providing circumstantial evidence in favor of the theory that there were two Starshield sats, USA 549 and USA 550, aboard the Starlink 13-4 launch.