I rarely do more than 24hrs anymore, and then again it’s usually because I’m too busy to eat, but I’ve done a few 36hrs and 48hrs in the past couple of years.
When I first started, breaking long fasts (24hrs+) required some care and thought if I didn’t want to feel sick or uncomfortably full. I found that a first small and light meal made up of easy-to-eat and easy-to-digest foods worked best for me.
So I usually would have a bowl of tomato soup, or something mostly soft and fat. Things like avocado, some smoked salmon, a yogurt, nut butter. Starchy carbs or things high in sugar usually made me feel like crap - anything more than a single toast was a no-no. Greasy or heavy stuff made me want to puke.
I’d have my regular meal maybe an hour after that small “breakfast” with no issue.
Now I’ve been doing mostly 22:2 for months, and breaking longer fasts don’t faze me anymore as long as I keep the volume reasonable.