I was asked, "When do I know I'm not a beginning programmer any more?"
I wouldn’t answer this question, because it’s the wrong question.
You should not ever want to know you’re not a beginner, because a true professional is always a beginner. The world in general, and the world of programming in particular, is so complex, so huge, that one lifetime is not long enough to stop being a beginner.
Your beginner’s mind is one of your most valuable tools. It requires you to look at each situation afresh, and to innovate. (Fundamentally, that's what the Agile movement is all about.) If you know children, watch how they use their beginner’s minds to conquer their world.
I’m very suspicious of people in the programming field who think they are no longer beginners. Myself, I’ve been programming for about 70 years, and I still consider myself a beginner.