Never heard of OKL until Daisy explained above! It gets confusing too when one factors in intermittent fasting, and the OMAD (one meal a day) days…
There are variations according to one’s state of health and fat-adaptation - and Dr. Phinney has frequently pointed out that 100% fat adaptation can take up to a year or more in some people with deranged metabolisms. So the first few months or seasons of keto are pivotal for just establishing basic fat adaptation. For those who are not insulin resistant, <20 grams net carbs is only for the first few weeks or months (up to a year in some) until one is mostly fat adapted. It was called the ‘induction period’ of the Atkins diet. Once fat adapted, 50 grams net carbs works great for me personally.
And as the body heals and changes, one can tweak things accordingly.
However, for those who are IR and/or on medications or who suffer from a tendency towards bingeing with sweeteners or carbs, keeping at <20 grams net may need to be a way of life for years until reaching desired recomposition, at which time enough metabolic healing has happened in order to do well with slightly higher amount of carbs, like 50 grams net, for maintenance.
There is a range in how rigid one’s keto approach is - and whether one is able to do intermittent fasting after having become solidly fat-adapted with a steady metabolic state (which for me at age 52 was around month 6).
So, some people can do really well (meaning, feel great and have steady body recomposition) by fluctuating between strict keto and lazy keto or LCHF throughout the week. Fat adapted people who do strength training tend to better with moderately more carbs, and young males who train may have even higher limits for carbs. Some endurance athletes with super powered metabolism may do fine with 150gr total (but many of us aren’t endurance athletes and are just regular mortals, etc).