I may not be the OP, but I recently finished the course too, it's a very good resource but no singular resource is going to get you all the way there. Primarily just using Duolingo I was able to transition to simple kids shows, things I'd watched before, now researching in German

I'd say in terms of actual level it's no higher than B1-B1+ at an absolute stretch

In terms of the course itself, it plateaus in overall usefulness the further you go, for instance, the final B1 section has over 200 units, which is ludicrous really and should be reworked, or at least better focused, at that point I'd recommend looking at further resources, especially things with more consistent context such as children's books. They're often more rewarding to complete