React Context vs. Redux Toolkit: When does state complexity demand Redux?

I'm building a new React application, and as it grows, the global state management is becoming more intricate. I've relied on the Context API for simpler shared states, but I'm starting to wonder if I should pivot to Redux Toolkit. What are the practical benchmarks or 'red flags' that indicate it's truly time to migrate from Context API + useReducer to a more robust solution like Redux Toolkit? Really seeking community wisdom on drawing this line effectively.