15 Survivor Mode maps to be released within the next 6 months. 
SEGA announced today the release date for their their first Alien: Isolation Season Pass add-on. Listed in the chart below is that release date, along with a placeholder for the remaining four add-on packs. I'll update this article as news comes in.
Each add-on pack for Alien: Isolation is scheduled to include three maps for that games Survivor Mode.
|
Add-On Pack |
Maps | Release Date |
| Corporate Lockdown | Severance; Scorched Earth; Loose Ends | October 28, 2014 |
| Trauma | Reoperation; Space; Overrun | December 2, 2014 |
| Safe Haven | TBA | January 13, 2015 |
| Lost Contact | TBA | February 10, 2015 |
| The Trigger | TBA | March 3, 2015 |