Here I can go to lg.com and there are phone numbers and a chat system. Ask there.
3D was sort of a bomb so good exchange for HDR. But HDR usually means a panel change. Are you sure the model numbers are an exact match including the trailing alphabetic letters?
I bought the LG 55EF9500 when it was first released. My buddy just bought the newer one without 3D. He has web os 3.0 and I noticed when he clicks on picture type he has HDR as an option. Does anyone know if the 55EF9500 will receive this option?

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