I generally remove them from the auto turner on bout day 18/19 but I continue to hand turn them until they externally pip, then I rotate the pip upwards and stop turning that egg...
A broody hen turns her eggs over 50 times a day every day all the way until the chickens hatch out....
They myth the chicken will get disorientated just doesn't fit natural incubation techniques, where the broody bird never stops turning and moving eggs, also the first chick to hatch normally bulldozes and rolls all the other eggs all over the place... In nature there is no 'lock down' or stopping of turning...