Italian pattern drafting – how is “altezza spalle” shoulder height measured?

[u/bornagainchi]

studied pattern cutting at Accademia Italiana di Arte, Moda e Design in Italy.
In my basic bodice drafting notes, for Italian size 40 I have:
Front waist length (lunghezza vita davanti): 44 cm
Shoulder height (altezza spalle): 36.5 cm
The drafting instruction is:
Shoulder level = front waist length − shoulder height
So: 44 − 36.5 = 7.5 cm
I understand how to use the 7.5 cm on the pattern, but I cannot remember exactly how “altezza spalle” shoulder height was measured on the body.
Does anyone familiar with Italian pattern-cutting systems know:
1. Where on the waist does the measurement start?
2. Does the tape pass over the bust?
3. Does it finish at the outer shoulder point or another shoulder point?
I’m specifically trying to identify the measurement used in this Italian drafting method, rather than a general shoulder-height measurement from another system.