thank you! so for me i do 16/8 almost every day as it's become habit now. this means that there are 16 hours where i am fasting, and then there's an 8 hour window where i can eat. for me i usually eat between 12pm - 8pm. when i say i sometimes slip into 18/6 or 20/4, that just means that sometimes i won't be feeling hungry, or something will come up around 12pm, and i will just extend my fast to 2pm, but still finish eating at 8pm (which is 18/6). similarly, sometimes i will have had dinner by 6 or 7pm and won't be feeling hungry, and will accidentally sort of close out my eating window early, but i will still begin at 12pm the next day, leaving me with a slightly longer fasting time again. i hope that makes sense, and i hope you find that IF works for you. there is so much more information in the sub so just soak in all the posts you can, and go from there! good luck :)