Road with the manager of my LBS this morning. He took a look at my back wheel and his only concern was that it was so new. His had the same amount of play but it was a lot older than mine. Said the play would hurt anything but that he would rather not touch it until I reach out to shimano. He thought they might send me a replacement wheel. One can hope.
That was the first time I rode with that guy and he is a beast. He and another lady left us in the dust more than once and I was doing everything I could to stay on his wheel. Really had to focus on staying as aero as possible, something I havnt had to really think about in the past.