Xbox 360-Xbox One and PS3-PS4 stat transfer issue
An issue with stat imports from Xbox 360 to Xbox One and from PS3 to PS4 has occurred during the past few days. Normally when you first play BF4 on the current generation of console under the same account as you did on the last gen consoles you will be prompted with a to import your soldiers and stats. This is no longer happening and the issue has been reported to DICE. At this point in time DICE hasn't put out a fix nor is there a user level fix at this moment in time.
BF4 Premium is still transferring to current gen consoles (PS3-PS4 and Xbox 360-Xbox One) without issue.
Cross platforms stat imports or Cross platform Premium imports such as Playstation to Xbox, or anything to PC are still not possible and will not be possible even after the any stat import fixes from DICE.