I do 48-60 with one day of eating. I eat whatever I want and whatever the amount feels satisfying. The point of this is not to restrict myself. I was lucky not to crave junk food as much though, but I think this has a lot to do with the fact that I don’t restrict myself on eating junk food, if I want to. And when I do break a fast, I always want to eat healthy food first anyways.
I calculated that I should be able to eat 3000 kcal on the alternate day, but even if I eat two chocolate bars and a bunch of normal food, I still end up in ketosis next day. I lost 15 kg in about two months, so my calculations are no accurate. I either burn a lot more than my calculated BMR of 1600 kcal or I eat a lot less than 3000 kcal. I should have lost something like 10 kg at best.