Survival DLC will be completely separate from update 1.4.
Tom Clancy’s The Division has seen its share of issues, ranging from the glitches to an unsatisfying single-player experience and shallow end-game. Massive is aware of this and has revealed more information on update 1.4 which will make sweeping changes to the overall experience.
In a new blog post, Massive said that update 1.4 will focus on balancing Gear Sets and weapons, providing a solo player experience, balancing the Dark Zone and PvP, focusing on time to kill and enemy difficulty, providing more relevant loot drops to the player, resolving currently known issues and providing Quality of Life changes (like removing the slow walk from the BoO to the Terminal and allowing weapon skins to not take up inventory space).
Update 1.4 will be out in October (with a special State of the Game presenting more information on September 13th) and it’s different from the upcoming Survival DLC with Massive focusing more on improving the overall experience rather than adding more new content. As a result, the Last Stand DLC has been delayed from Holiday 2016 to early 2017. Stay tuned for more information on upcoming changes with The Division in the meantime.