I am in similar situation. I called and was told the I-485 officer should adjust my status whichever (EB1 or NIW) comes first. The lady I talked to actually matched up both my I-140 to my I-485. I called in sometime later, another lady told me a different story and even asked me why I applied two I-140s. I told her what I was thinking. Seems not every USCIS person knows what he/she is taling about.