Greetings,
This is your friendly 6 month warning that Asterisk 11 will be
reaching an official end of life state on October 25, 2017. As many
of you know, for the past 6 months Asterisk 11 has been in security
fix only mode. This means it currently does not receive bug fixes,
but it does receive applicable security fixes and will continue to do
so for the next 6 months.
If you are still running Asterisk 11, this is a great time to start
preparing for a move to the latest LTS branch, 13, as a forward
migration path. You can read more about Asterisk’s branch and
versioning policy as well as relevant version sunset information on
the Asterisk wiki [1].
Best wishes to you all, and happy upgrading. 
[1] https://wiki.asterisk.org/wiki/display/AST/Asterisk+Versions
Matthew Fredrickson