I did 16/8 and my supply stayed the same( I pump) I did it for like a month & a half though
You totally can. It’s not like you’re starving yourself you’re just eating later in the day. As long as you still get your calories in for the day during eating time then its totally fine
I would say not because your body needs a specific amount of calories to maintain your supply and by fasting you send your body into essentially starvation mode which could affect you supply negatively. I don’t think it would be worth the risk personally.