Assume that I create a stream BASE and then refer to this stream in a number of “derived” streams S1…SN by using the “stream” target in the definitions of S1…SN. First I have to compile BASE to get a hash H which I then specify in the definitions of S1…SN. What happens if I update BASE and now want all of S1…SN to automatically reflect my change? I would have to compile the new version of BASE to get a new hash HNEW. And then I would have to manually replace H by HNEW in the definitions of S1…SN and recompile each of them?
This page on Version Control should answer your question.
When you edit and compile a new stream, you are essentially creating a new stream with a new stream hash. You will need to update any streams which reference this edited stream if you want them to refer to the new version of the stream.