SpaceX halted the USSF-259 launch attempt before fueling Monday night and shifted the classified U.S. Space Force mission to a backup window opening 6 p.m. PDT Wednesday from Vandenberg.
No public reason was given for the scrub. The Falcon 9 is set to fly south from Space Launch Complex 4E and deploy its payload into low Earth orbit at roughly 80 degrees inclination.
B1097 is assigned to the flight for its 13th mission, with a droneship landing attempt about 8.5 minutes after liftoff on Of Course I Still Love You in the Pacific.
USSF-259 is SpaceX's third launch in a month under the Space Force's NSSL Phase 3 Lane 1 contract, following USSF-366 on Aug. 15 and USSF-153 on Sept. 10; another mission, R-3, is listed for Sept. 27.