For sure nothing less than 1800. I have my diary set at 1260 and add whatever I pump which is always around 530-600 extra. So it comes out for my daily goal 1800-1900. I try to stay closer to 1800 cause I don't lose if I am closer to 1900. it falls below 1800, I'll eat a little extra snack. My supply has been great with it set up like this. LO is 4.5months old and ebf. You just gotta play with numbers and see what works for you.

I think observing your body is the only way to know. Low supply, grumpy, feeling terrible? Eat more calories! Gaining weight? Eat less calories! Last time I gained 6lbs by blindly consuming 500 extra calories everyday (or more!) regardless of a perfectly adequate supply. This time I will be a bit more aware of what my body/baby actually needs and if I see the scale go up (or refuse to come down), I will reevaluate!

If your body considers itself starved you will not lose weight. It will take a few of weeks of eating correctly before you will be able to diet again. Eating at around 1800-2000 a day is a good start. You will need a while to establish what your maintenance should be with breastfeeding added as an exercise and when you are no longer gaining or losing weight you'll know to deduct calories from there. Lots of breastfeeding mums feel hungry a lot of the time, but make sure you drink a glass of water before eating, as often thirst is mistaken for hunger and mums often underestimate their needed fluid intake when feeding.