No. IIRC EA mentioning March 2017 was so that they don't get fucked over if they don't hit their holiday target. It's just a buffer.
March 2017 is the end of their fiscal year. They were making an official call to investors, and the release of a Mass Effect would have a material impact on their bottom line. So they added guidance that said it would be out by the end of their fiscal year. It's all about providing insight to their investors (read: shareholders) as to what their financial situation will look like in FY 2016.
So, yes, it could get delayed to early 2017, but if it goes beyond the end of March, they start getting in real trouble. Telling investors when a game is coming out is wildly different from telling like the games press. Lying to investors or misleading them can lead to legal consequences.
That's not to say it couldn't conceivably be delayed, it's just a much bigger deal than if they had told IGN or Gamespot that it would be out in March 2017 and it slipped to May.