I do 18:6 or less on weekdays but up to 12:12 on weekends because it’s nice to be able to eat with my family throughout the day. I realize 12 hours isn’t considered “really” fasting but I still like the framework and it feels like that way the days get closed out. I think coming up with a sustainable plan is the most important part, and that might include this being a ramp-up period for you for work-day fasting, or a more hybrid model as the long-term answer.
If this is something you want to do, long term, I think you have to do what is sustainable for you. If that is 16, 17, or 19 hours, instead of 20, so be it. If you can do longer fasts on weekends, that’s a bonus.
It’s better to make small adjustments that fit YOU, than to give up completely because the 20/4 doesn’t work for you during the week. That’s what happens with some people, they get an “all or nothing” mindset, which just isn’t real life (for most things).
I’m super flexible, and I believe that hunger should not be ignored. Obviously there will be some moments of hunger while fasting but if having a glass of water and chewing some gum or ice doesn’t quell the feeling, then your body is trying to let you know that it needs sustenance and what you’re doing isn’t enough - that could mean that you’re doing too much and your food input should be going up on those days, or that what food you are eating isn’t the right stuff to make your body satisfied long-term. If I were you I would eat early, and if it’s consistent try to figure out the cause. And it could be that your body just doesn’t vibe with 20 hour fasts, and that’s perfectly fine too!
If you’re going to do the 20 hour fast dont forget to drink a ton of water and replenish your electrolytes, I fill my hydroflask up and put in a couple tea spoons of salt and lemon to so my sodium level doesn’t get too low. Also to help really curve my hunger I have at least 1 cup of black coffee but green tea will help too. Just finding the things that work for you and so far these have worked great for me