Hi DBK,
Yes you’re right. It is a right way changing shape for each note.
But I think that this shape is found by letting the lips respond to the pressure (not the volume obviously). I think that it is the sensation of each pressure for each note that is important to memorize. The lips will find the way to vibrate sympathetically in the tube function of this pressure. I do not have to think too much at my embouchure, I let my lips to react freely with the pressure. If I think too much on the best position of my lips (corners inward) then it is too tense or too tight. Yes the lips have to vibrate freely like the vocal cords; but do you think how to set your vocal chords when you talk or sing? I do think so, for me it is more complicated and based essentially on feeling that are unmindful.
I think that it is the Morrison’s message great artist and trumpeter.
Best regards.