The Fasting Method podcast talks about this protocol as well. From what I’ve seen, you should try this if you’ve successfully been able to do 16:8, then 18:6, then 20:4, then OMAD… 30:16 is talked about as the next step up / challenge from there.
I skipped 30:16 and went from 23:1 OMAD to 3x42 and I will say, that leap wasn’t as difficult as I imagined. Of course, I am only a couple days in :)
Very good protocol for losing weight, the real key is on the refeed to make sure you are eating clean. A cheat meal now and then wont do much, but if you are eating refined carbs in all your windows, progress will be slower.