Barista Expert
Rare9.8%GrindOptional
Half way through mastery
Once you complete the game an individual will speak to you. You'll note certain days and the idea is to go back and replay them. These days are Sept 22, 24, 29th then Oct 18.
I would highly recommend after you replay each of these days to let the next day start then save your game before loading a different chapter. It initially didn't work for me until I did this.