I think there are 2 answers here.
- In early stages you should up the fat (similar to trying to hit the fat numbers) because your hormones will not really let you get at your stored fat (they mostly just make you feel bad and make you desire cookies). You might also end up in “metabolic slowdown” land if your psychology (not satiety) is the culprit that is making you keep fats low.
- After a couple of months of pure keto I still think you are trying to hit the fat numbers but, due to satiety, it should be a combination of dietary fat and the fat from your body (which can now be accessed easily after low insulin for a long time because of limiting carbs).
So, if you are monitoring all of this, you should be able to see regular weight loss proportional to the amount less you are taking in after a few months when you let eating to satiety limit intake.