United Launch Alliance may be forced to shift the launch of its new Vulcan Centaur rocket and its moonbound commercial lander from Christmas Eve to the new year.

The announcement by ULA President and CEO Tory Bruno came this weekend after an attempted wet dress rehearsal on Friday at Cape Canaveral Space Force Station ahead of the mission dubbed Certification-1.

The test aimed to roll the rocket out from the Vertical Integration Facility at Canaveral’s Space Launch Complex 41, run through the launch day countdown including the fueling of cryogenic fuel, and roll it back to the VIF.

“Vehicle performed well. Ground system had a couple of (routine) issues, (being corrected),” Bruno wrote on X. “Ran the timeline long so we didn’t quite finish.”

The inaugural United Launch Alliance #VulcanRocket is standing atop Space Launch Complex-41 at Cape Canaveral to undergo an extensive Wet Dress Rehearsal ahead of #Cert1.

Learn more about this test in the #CountdowntoVulcan: https://t.co/fyGyXCFb68 pic.twitter.com/fVKEaEF0jN

— ULA (@ulalaunch) December 8, 2023

Bruno said in the post he’d want a full wet dress rehearsal before the rocket’s first flight, and as such, “XMAS eve is likely out.”

The Vulcan Centaur is ULA’s replacement rocket for its Atlas V and Delta IV family of rockets. Its first launch, which was originally targeting 2021, has gone through a series of delays, but now looks to finally put ULA on the path to begin servicing more than 70 planned launches on the new rocket over the next five years.

While the original targeted window for the flight has three options from Dec. 24-26, Bruno noted the next available window would open Jan. 8. and would have four days of launch opportunity. The launch times for either month’s window are in the early morning hours after midnight.

Those windows are defined by the needs of the primary payload, Astrobotic Technology’s Peregrine lunar lander, which is slated to be the first of NASA’s Commercial Lunar Payload Services contract landers to launch. Its mission profile with required trajectories to allow for a moon landing dictate when Vulcan can launch.

ULA’s stable of existing rockets is getting thin with a lone Delta IV Heavy left that’s slated for launch next year and 17 Atlas V rockets, all of which are assigned to missions that will be done launching by the mid-2020s.

That includes using eight more Atlas V’s for the first few hundred of 3,236 of Amazon’s Project Kuiper satellites, a competitor to SpaceX’s Starlink constellation. Vulcan Centaur will then get the lion’s share of that constellation’s missions with another 38 launches as the Atlas V’s run out.

ULA is building out a second rocket processing facility at SLC-41 to handle what it expects will be at least two launches a month by 2025.

It will be a much higher pace than the limited action ULA saw in 2023. If Vulcan pushes to 2024, the company will have only flown three times with last June’s penultimate Delta IV Heavy launch and a pair of Atlas V launches in September and October.

That amounts to less than 5% of the launches on the Space Coast for the year with SpaceX flying all but four of the 68 orbital launches so far from either KSC or Cape Canaveral for the year. Relativity Space added a lone launch with its 3D-printed Terran 1 rocket in March.