if that is the case; if it becomes so; when it becomes so
そうなると困ってしまう。
If it comes to that, I'll be in trouble.
そうなると全員に影響が出る。
If that happens, it will affect everyone.
計画が変わるとそうなると、すべてやり直しになる。
If the plan changes and it comes to that, everything would need to be redone.