When in doubt, don't forget our BYC learning Center found on the home page. This is a quote from How to hatch eggs.
Turning
Turning 3 times a day seems to be adequate for chicken eggs. Turning is essential in the early stages. For the last 3 days of incubation when the bird is preparing to hatch, do NOT turn. If not turned to a fresh position frequently during the early stages, the developing embryo touches the shell membrane and sticks to it causing abnormal growth. Turning the egg aids these movements within the egg, and mimics what a mother hen would do naturally.
It is important that the eggs are positioned correctly, with the small side tilted downward. This is the way an egg lays naturally unless it is shaped more oval. The chicks will turn inside the egg and will be able to pip the internal membrane and get into the air cell. Moving them around during that time messes them up and can cause them to hatch on the wrong end or more in the middle.
It is really good you asked here but when in doubt I always refer to the information on the website as I feel it has been published and tested and is sometimes more reliable than information some people are apt to give.
Good Luck with your hatch and let us know how it goes.