NASA on Friday hauled its repaired moon rocket from the hangar back out toward the pad at Kennedy Space Center in Florida in an effort to launch four astronauts on a lunar flyaround next month, according to the Associated Press’ reporting from Cape Canaveral. The move came for the second time this year as NASA worked to recover schedule after prior technical problems with the rocket.

The Artemis II launch is tied to repairs NASA completed and to whether conditions at the launch site remain favorable. If the latest fixes hold and other steps proceed as planned, NASA said the Space Launch System could blast off as early as April 1 from Kennedy Space Center, where the mission’s launch pad sits.

NASA began the relocation overnight, starting a slow 4-mile (6.4-kilometer) trek with the 322-foot (98-meter) rocket carried atop a massive crawler system that has been used since the Apollo era. The move was slowed by high winds for several hours, but NASA completed the trip by midday, after about 11 hours from start to finish.

While technicians worked at the pad to resolve issues that cropped up during earlier testing, NASA said hydrogen fuel leaks were addressed at the pad. The earlier helium problem, however, could only be fixed in the Vehicle Assembly Building, which required NASA to roll the rocket back at the end of February before returning it for further processing.

The Artemis II crew is scheduled to enter quarantine in Houston this week, setting up launch operations ahead of the flight. The mission calls for three Americans and one Canadian to travel in the capsule to make a flyaround of the moon and then come straight home without stopping, a profile that keeps the flight from including a landing on the lunar surface.

NASA’s Artemis program, which aims for lunar landings in 2028, represents the next step in U.S. crewed moonflight after Apollo’s last astronaut mission in 1972. This Artemis II attempt has already slipped once: hydrogen fuel leaks and clogged helium lines forced about a two-month delay, pushing the timeline that NASA is now trying to reestablish with the April target.

Marcia Dunn reported for the Associated Press Health and Science Department that the Artemis II crew was placed into quarantine in Houston and that NASA moved the repaired rocket toward the pad for an early April launch.