It takes 2-4 weeks to convert one behavior into a new habit. A meal plan is not a behavior, it is about 80 behaviors. If you do not learn how to eat for your life then it cannot stick and then unfortunately the results you accomplished are not maintainable.
Here is the first goal to try and accomplish for your first 2 weeks of lasting lifestyle habit changes. Learn to recognize the difference between satisfied and full. It takes 20 minutes for your stomach to send the signal to your brain that it is satisfied. Research shows that we eat to uncomfortably full in 12 minutes. We are fast eaters.
Slow down and savor the flavor of your food.
I didn’t even tell you to avoid eating anything. Deprivation does not work!