According to EA, Battlefield 4: Second Assault will be one of the first pieces of DLC that will be available on the Xbox One platform. The DLC will be available when the console launches on November 22 nd this year. So you can unbox your Xbox One, hook it up to the Internet, and make it the very first thing you download if you want.
Second Assault will include four Battlefield 3 maps that are “re-imagined” for Battlefield 4 . The pack will be free for all Battlefield Premium members. It will be a timed exclusive for the Xbox One, but will later come to other platforms. Unfortunately, no launch dates or pricing have been given for these platforms at this time.
Battlefield 4 will launch on October 29 th for the PlayStation 3, Xbox 360, and PC. It will be a launch title for both the PS4 and Xbox One when they release on November 15 th and November 22 nd respectively.
Source: Polygon