I have had a couple of meals that would be considered off plan. I live in Kazakhstan and we celebrate Nauryz which is Persian New Year. I was invited by my local friends to a special luncheon which was a table full of local delicacies which are only prepared for this day. I had a few bites of each to show respect to my hostess. I kept the eating to under an hour. So I guess I had a "reward" meal of sorts. It did not derail me. I was able to return to plan at the next meal.