'Basics tutorial' issue

In the _Defining the service_ section, there's this text:
> Once the client has finished writing the messages, it waits for the server to read them all and return its response.

However, in the _Client streaming RPC_ section from the [Core Concepts](https://grpc.io/docs/what-is-grpc/core-concepts/) documentation, it says this:
> The server responds with a single message (along with its status details and optional trailing metadata), typically but not necessarily after it has received all the client’s messages.

Both statements cannot be correct.