As far as I understood it, you will get an "advised spread" for attributes when picking a class.
Then, in the attribute tab you can either keep it, or modify it to get different attributes.
Since they do not seem to change the point buy system itself, I completely expect to be able to hit 17 in an attribute of my choosing.
Though 17 makes only sense if you are planning for a feat that gives you +1 on an attribute - or if you have another uneven attribute.
And as far as I have heard, Actor and Resilience are the only once that could give you +1 charisma.
Since they all already have charisma saving throws, that leaves actor, which needs you to be proficient in deception and/or performance to be actually useful.
