Completely guessing here, but I would think that the minimum 16 points (If i've got that right) would be around 1500 calories a day, and then increase as the points increase, as if you are taller, a man, breastfeeding or weigh more, then you use more calories on a daily basis, and can therefore eat more and still lose weight. No idea if that's right but in my head that's how it works!
On the core plan it's less about the calories and more about eating foods to fill you up and keep you satisfied longer. When i've worked out how many calories i've eaten on a day on core then it can range from between 800 a day to 2000 - and I still lose weight!