This indeed moved around.
You define your S-N curves in the Fatigue study now, so don't worry about them for your reference studies, once you add an event in a fatigue study it will give you an option to choose S-N curves.
It actually makes more sense because these curves are only used in fatigue studies, but at the same time it moves a material property from its perhaps most logical place which is the materials dialog box.
A little good, a little bad, all searching around finding it again. lol.
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