United Launch Alliance is set to try again to launch a Delta 4-Heavy rocket and a classified U.S. government spy satellite Thursday after delays of more than three months caused by persistent issues with the mission’s launch pad.

The 32-story-tall mobile service tower at the Delta 4’s launch pad at Vandenberg Air Force Base in California was retracted away from the rocket Thursday in advance of a planned liftoff with a top secret National Reconnaissance Office payload.

The next launch of United Launch Alliance’s Atlas 5 rocket with the U.S. Air Force’s fifth Advanced Extremely High Frequency communications satellite, previously scheduled for Thursday, has been delayed to no earlier than July 12 to replace a failed battery on the vehicle.