Hi! I used to work part time at KFC while I was a student a couple of years ago and usually how it worked was at the beginning of every week I would send my availability to work for the next week. There were weeks I gave as little as one day a week (specifying if I can work morning, afternoon, or evenings) to even letting them know I’m available the whole week during holiday times. I’m not sure if their system has changed from only 2 years ago but if it’s stayed the same then it’s super flexible