sorry for the perhaps dumb question - but what are lines notes for?
Not a dumb question! This is a don’t-apologize-for-your-questions zone.
Line notes are just that: notes taken about the lines in the script as the actors rehearse to help them get their lines word-perfect. Sometimes they’re redundant because they know they got it wrong, sometimes they’re very helpful because they didn’t realize that they were skipping a sentence or not giving their scene partner (or stage manager) a cue, etc.
Here is an example of some of mine











