Second Assault is indeed coming to Battlefield 4 on February 18th, Naval Strike announced

That leak on a Germany Origin site has now been confirmed by DICE as Battlefield 4: Second Assault will be coming to Premium users on February 18th. If you aren't a premium member, March 4th is the date you'll be able to pick it up.

Not only was a date confirmed for Second Assault, DICE has gone and announced the third DLC. Titled Naval Strike, this water themed DLC will be coming out sometime in March. Besides new weapons and vehicles, four new maps will be delivered with Naval Strike. The map names are: Lost Island, Nansha Strike, Wave Breaker, and Operation Mortar.

Battlefield 4 still does need some fixing, but those looking for new content will be happy to see that there will be two DLCs in a span of two months coming out.