I think getting C1/C2 certification doesn't really test for that kind of thing, but instead, to my knowledge, being able to communicate increasingly complex ideas in a relatively sterile environment. So, you probably could get fairly automatic when debating about economics or having general conversation or something abstract at home, but in France you probably won't be automatic until you spend a sufficient amount of time practicing all the little things in daily life. This is something I will struggle with to unless I immerse myself someday, but being able to say what you want generally is definitely good enough to at least survive at live decently well. Good luck, sounds like what you're doing is the best possible!
Like most skills, language proficiency work in steps, and you are usually only able to see the next step, the rest goes above your head.
In the case of language, the first step is learning the words and grammar. This can be tested. But there is a whole world beyond that. I realized it when talking about the Japanese language with a girl she didn't even talk about things that come up in tests, like vocabulary. Instead she talked about how to talk to different kind of people, idiomatic expressions, how to convey emotions, even the quirks of writing text messages. She was on the next level, the part about describing things was already a given, not something worth talking about. There are certainly many things lying beyond that, maybe accent, body language, a point where the distinction between language and culture starts to blur...
An interesting thing is that AFAIK, there are no tests that evaluate the proper use of "bad" language. French (my native language) is famous for its colorful swearing. And you can't really call yourself fluent if you don't know how to do it. Proper use of casual and even offensive language, is, I think, an important skill that most foreigners lack, in any language, and yet, most test don't go below business level speech.
It is when you think in this language. Yes. Exactly. You need to become fluent in thinking in a language to be fluent in real life situations.
And its also kinda cool to be able to think in two language. Its kind of a superpower :)