when I do my character breakdown (who appears on what page and when do they leave), I will divide things into clear shifts (lots of characters arrive or leave, a piece w only a handful of folks or there is a major thematic change, etc) to plan rehearsals - and then sit w the director to work on the calendar and, well, the director often wants to use my chart to label scenes and use for rehearsal shorthand (scene 1 is pp 1-13 up to Xs entrance, sc 2 is pp 13 from Xs entrance to p 15....etc translates to Wed 1-3 scene 1, 3-5 Scene 2 so people can do their own work as well as work on the go.
just read for beat shifts and character presence/absence.