Depends on the phase of construction. The pressure hull will be fully complete before being floated for the first time, with most (if not all) systems installed. But there still may be operational testing, training, etc. going on that is part of the construction process. Those types of things can take place waterborne (and in some cases are required to), which frees up space for construction of the next hull to begin.
…in hospice since February 2023.