There are many schools of thought as to re-feeds, with the aim of optimizing insulin and periodically restoring glucagon.
Mauro Di Pasquale generally recommends hi-carb re-feeds every Saturday and Sunday, with low carb, high (good) fat and high protein Monday through Friday.
Rob Fagin, who wrote Natural Hormonal Enhancement, advocates 3 days of low carb, high (good) fat and high protein, except for the last meal of day three which is high carb, low fat and low(ish) protein, followed by 4 days of low carb, high (good) fat and high protein, except for the last meal of day four which is high carb, low fat and low(ish) protein. That three day/four day cycle continues.
Both advocate staying very low carb for an initial period of about 12 days, prior to adding carbs. For Di Pasquale, I believe he advocates up to 50 grams of carbs (initially), while Fagin targets 20 to 25.
Both look at net carbs (total carbs – fiber), and suggest fibrous carbs (e.g., celery and broccoli) rather than starchy carbs.