Why doesn't Firefox from Canonical get updated?

[Chris]

I'm still on version 49.0. I received an email today from US CERT that
49.0.2 is out. I would think I at least need to update to 49.0.1 from
Canonical but Synaptic shows no updates available. The version I have
installed is

chris at localhost:/var/log$ apt-cache policy firefox
firefox:
  Installed: 49.0+build4-0ubuntu0.16.04.1
  Candidate: 49.0+build4-0ubuntu0.16.04.1
  Version table:
 *** 49.0+build4-0ubuntu0.16.04.1 500
        500 http://us.archive.ubuntu.com/ubuntu xenial-updates/main
amd64 Packages
        500 http://security.ubuntu.com/ubuntu xenial-security/main
amd64 Packages
        100 /var/lib/dpkg/status
     45.0.2+build1-0ubuntu1 500
        500 http://us.archive.ubuntu.com/ubuntu xenial/main amd64
Packages

-- 
Chris
KeyID 0xE372A7DA98E6705C
31.11972; -97.90167 (Elev. 1092 ft)
20:01:21 up 1 day, 11:26, 1 user, load average: 0.10, 0.16, 0.11
Ubuntu 16.04.1 LTS, kernel 4.4.0-45-generic #66-Ubuntu SMP Wed Oct 19 14:12:37 UTC 2016
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