Fat Adaptation and Backsliding

You say it takes about 2 to 6 weeks to become fat adapted. How long does it take to go back to being insulin resistant? If I eat off protocol for 1 day, or 1 week, will it be easier to get over my cravings/become fat adapted once I get back to eating on my protocol than it was the first time? Or am I starting over if I ate flour and sugar for a day or 2?