Follow the interviewer and move on unless they ask you to finish the structure.

Interruptions can reflect time management, interviewer style, or a deliberate shift in the case. They are not automatically negative feedback.

If you have already communicated the key branches and the interviewer asks about the market branch, answer the question rather than insisting on finishing every sub-point.

Stay flexible. If the missing part becomes relevant later, you can bring it back naturally. If useful, this guide on first-round consulting interviews gives more detail.