Flew last night LGA/DTW and this new policy was confirmed by a FA. She said effective 5/24, I think it was. She said - specifically - FC - THEN ELITE - THEN GENERAL BOARDING. She told me that this procedure is being and has been tested at certain airports. That would explain why some of us have seen this and some haven't. (I haven't). As posted above, this is supposed to have proven to be 5 - 10 min faster.