@Luciano I assume you’re asking whether your existing active contracts need to be upgraded when you want them to use the new version of your library. Please correct me if I misunderstood your question.
The answer is an emphatic “Yes, that’s exactly what it means” and I would argue that’s exactly what you want in a DAML-like smart contract setting. If it wasn’t like this, you could change the potential consequences of a contract after its signatories have agreed to it by virtue of changing a function in your library, which then changes the behavior of the underlying template. However, that is at odds with one of the fundamental principles of DAML: If you sign a contract, you authorize all its potential consequences, which might make you a signatory of further contracts without your explicit signature being required.
Does that make sense and does it answer your question?