Part of it is a difference in philosophies. SpaceX operates with a sense of urgency and sees no reason to dawdle. Since it is worth doing, do it right away. In fact, the company needs to get the rocket stack out of the way so that they can start preparing for the next launch, which may be less than a week away. It is how to keep up a high launch cadence. Since the Atlas rocket does not have a high launch cadence, there is no hurry getting the stack out of the way of the next launch. There is less sense of urgency in the ULA corporate culture. Northrup Grumman’s culture may also lack the same sense of urgency.

Another part is that this is the first manned flight, and greater care must be taken to assure that the procedures are not only followed but are truly correct. A little extra time is placed in the schedule to account for problems that occur because this is the first time. This is the first manned flight for this entire team. In the future, they may be able to take two or three weeks off this schedule, once they are familiar and comfortable with the operation.

Interesting that they are stacking a booster in Feb for a launch in April. Unlike the SpaceX CRS mission this weekend, which was probably stacked earlier this week.

Ray Van Dune: Typo fixed. Thank you.

As for future Starliner launches, I am pretty sure they will fly on Vulcan.

Ps. Just a nit: “ULA has begun to assembly…” should probably be “ULA has begun to assemble…”