Hello,
Here are the Public Documents available for SEP 12.1.2
Symantec™ Endpoint Protection and Symantec Network Access Control 12.1.2 Installation and Administration Guide
https://www.symantec.com/business/support/index?page=content&id=DOC6153
Symantec™ Endpoint Protection and Symantec Network Access Control 12.1.2 Client Guide
https://www.symantec.com/business/support/index?page=content&id=DOC3719
Symantec™ Endpoint Protection 12.1.2 Getting Started Guide
http://www.symantec.com/docs/DOC4322
What's new in Symantec Endpoint Protection 12.1.2
http://www.symantec.com/docs/HOWTO81091
System Requirements for Symantec Endpoint Protection, Enterprise and Small Business Editions, and Network Access Control 12.1.2
http://www.symantec.com/docs/TECH195325
Symantec Endpoint Protection for Macintosh Frequently Asked Questions
http://www.symantec.com/docs/TECH134203
Upgrading or migrating to Symantec Endpoint Protection 12.1.2011 (RU2)
http://www.symantec.com/docs/TECH197426
Hope that helps!!