12:12 is fairly easy to do, but it doesn’t offer many health benefits. You may want to consider increasing your fasting window. What you propose—waking at 10 am and stopping eating at 6 pm—would bring you to a 16:8 routine, and you would begin to see some benefits. Give it a try.However, I’m not sure how to answer your actual question. Fasting different times on different days might give you a good long fasting window one day, then an insufficient one on another day. However, I would recommend working to make fasting fit your schedule, regardless of whatever you choose to do.Finally, the removed post here referred to an author who for some reason seems to be persona non grata here, but whose books are really great references. I’d recommend checking them out.