Handling Most statements

Why did she change the second premise "S most L" into a some statement? I understand how she did it, but I do not understand why she did it in the first place when it seemed perfectly fine to me to just take the first premise and second together without it. For example, why could it not have been: S --> ~AP S most L to conclude: L most ~ AP ?? Please correct my understanding of quantifying rules: 1) I thought that when I combine a S/N statement with a most statement, that I DO NOT have to change the final statement into a some statement (which is what I think the instructor did).. but rather that I can leave it as a most statement 2) If I want to, I CAN change most statements into some statements. I know I am REQUIRED to if I try using the exception rule with 2 most statements, but am I also able to with a singular most statement for the sake of it?