This is very much an individual thing. Some lucky people who don't have other complicating issues can have their guts heal and regain a good deal of insulin sensitivity, so that the odd carb-heavy meal doesn't derail their food plan or cause extreme reactions. Others, and maybe the majority, continue to have hyperinsulemia and the resulting reactive hypoglycemia in response to more than a modest amount of carbs if the dietary change is the only one they make. I'd be curious to see the results of even an informal poll of people who've been low-carbing at least one year and are within 10% their goal weight about this question.