Maybe I can add to that.
Part of the work we do at the enterprise architecture review board, where these major initiatives come through as part of their governance process, is to ensure that alignment and interoperability. One of the recommendations we make is to make sure that there are interdepartmental teams, including governance teams, that are working together to allow for that alignment and that testing.
Also, maybe just to add to the previous question, that is part of some of the benefits of what agile does. It allows you to get some of those answers, some of those mitigations, out early before you get to the end and realize that things aren't working together. There are benefits to that side of the equation.