The good news is that it's about your natural rhythms rather than a fixed protocol. In other words, in my opinion you can't do IF wrong.

I happen to think random variation is the most natural pattern. I don't IF every day; I don't eat every day. Some days I have 2 meals; many days I have one. My meal(s) may be in the morning, afternoon and/or early evening although in my case I don't like to eat after 6 pm as I like to clear my stomach before bed (hiatal hernia.)

Some people perform best with a small meal about 2 hours before peak exertion; I do best fasted with my main meal 2-3 hours after peak exertion. I can comfortably be active even if I haven't had solid food for 40+ hours.

I recommend lots of experiments and then you should do what you like best.

In terms of the benefits, I don't think the details matter too much. The ideal window and timing is what works best with your schedule and training. People have achieved results with a wide range of protocols. The balance depends on how you feel and whether you are struggling with workouts etc.

The official advice I believe would be 14 hour fasts, breaking them just after your intense workout. That usually dictates when people fast. Others have problems eating late that affect their sleep, in which case that may be more important. Obviously the more frequently you fast, the more fat you are likely to lose, but it may come at an undesirable cost in terms of your energy levels. Most settle into a regular window every day, but you will do little harm in occasionally eating more one day if you feel you need to. The 10 hour eating window for women however is really plenty of time.

Further gains can be got from adding a longer fast once a week (or less often even). This will probably help with additional benefits beyond fat loss, but should certainly help there if necessary. Again though, if you end up eating too little over the whole week then it becomes counterproductive.

As you can see, if there is an ideal approach we don't know what it is yet. Personally I prefer variety. Most weeks I'll not eat for one day, the rest of the time I'm eating in a window, usually waiting until lunch to start but sometimes I'll earlier and stop well before bed. Some days I'll be nibbling throughout the day - a lot depends on what food I'm eating, I don't really have 'meals' that often any more.

what ever you do, don't allow the body to know when you Fast, it has to be irregular and random. Don't develop a pattern. And I believe Winter is better than Summer, although possible, as famine occurs in any season.

I do all my eating in a one hour window in the evening, then nothing again until the same time the next day (a 23/1 fast). It's worked great for me — combined with paleo I've lost 20lb since January and feel great.

(For reference, I'm currently 215lb male with a target weight of 200.)