Building code requirements are not a test at the end of design. They decide how many exits a worship room needs, whether the building must be sprinklered, and how large it can be, and the decisions are far cheaper to make on purpose at the beginning.
Most owners assume that getting the drawings done is the finish line. It is not. The period between completed construction documents and an issued building permit is one of the most consequential and least understood phases of any project, and how well you navigate it determines when your contractor can actually start.