I can easily do a 5-6 hour food window. The key is to eat, mid-morning or even noon if I'm busy, a big serving of meat/eggs with a small side of low carb something.

Then, if the end of the window approaches and I'm still hungry, I have a snackier type meal, like a smaller portion of meat, some cheese, and some raspberries (the lowest carb fruit.)

This lets me cruise into bedtime with an empty stomach, which is good for sleeping, and gives me maximum fasting/healing time.