diff --git a/config/production/daily.json b/config/production/daily.json
index fb7bb6e1..d7c2c410 100644
--- a/config/production/daily.json
+++ b/config/production/daily.json
@@ -3,8 +3,7 @@
         "applabel": "mozmill_daily",
         "branches": [
             "mozilla-central",
-            "mozilla-aurora",
-            "mozilla-esr31"
+            "mozilla-aurora"
         ],
         "platforms": [
             "linux",
@@ -194,45 +193,6 @@
                         "windows && 8.1 && 64bit"
                     ]
                 }
-            },
-            "mozilla-esr31": {
-               "locales": [
-                    "de",
-                    "en-US",
-                    "ru",
-                    "zh-CN"
-                ],
-                "testruns": [
-                    "update",
-                    "functional",
-                    "remote"
-                ],
-                "platforms": {
-                    "linux": [
-                        "linux && ubuntu && 14.04 && 32bit",
-                        "linux && ubuntu && 14.10 && 32bit"
-                    ],
-                    "linux64": [
-                        "linux && ubuntu && 14.04 && 64bit",
-                        "linux && ubuntu && 14.10 && 64bit"
-                    ],
-                    "mac": [
-                        "mac && 10.6 && 64bit",
-                        "mac && 10.7 && 64bit",
-                        "mac && 10.8 && 64bit",
-                        "mac && 10.9 && 64bit"
-                    ],
-                    "win32": [
-                        "windows && xp && 32bit",
-                        "windows && vista && 32bit",
-                        "windows && 7 && 32bit",
-                        "windows && 7 && 64bit",
-                        "windows && 8 && 32bit",
-                        "windows && 8 && 64bit",
-                        "windows && 8.1 && 32bit",
-                        "windows && 8.1 && 64bit"
-                    ]
-                }
             }
         }
     }
diff --git a/config/staging/daily.json b/config/staging/daily.json
index af7bc8e4..0ddb2f0e 100644
--- a/config/staging/daily.json
+++ b/config/staging/daily.json
@@ -4,8 +4,7 @@
         "branches": [
             "mozilla-central",
             "mozilla-aurora",
-            "mozilla-beta",
-            "mozilla-esr31"
+            "mozilla-beta"
         ],
         "platforms": [
             "linux",
@@ -185,41 +184,6 @@
                         "windows && 8.1 && 64bit"
                     ]
                 }
-            },
-            "mozilla-esr31": {
-                "locales": [
-                    "ar",
-                    "en-US",
-                    "zh-CN"
-                ],
-                "testruns": [
-                    "update",
-                    "functional",
-                    "remote"
-                ],
-                "platforms": {
-                    "linux": [
-                        "linux && ubuntu && 14.04 && 32bit",
-                        "linux && ubuntu && 14.10 && 32bit"
-                    ],
-                    "linux64": [
-                        "linux && ubuntu && 14.04 && 64bit",
-                        "linux && ubuntu && 14.10 && 64bit"
-                    ],
-                    "mac": [
-                        "mac && 10.6 && 64bit",
-                        "mac && 10.8 && 64bit",
-                        "mac && 10.9 && 64bit",
-                        "mac && 10.10 && 64bit"
-                    ],
-                    "win32": [
-                        "windows && xp && 32bit",
-                        "windows && 7 && 32bit",
-                        "windows && 7 && 64bit",
-                        "windows && 8.1 && 32bit",
-                        "windows && 8.1 && 64bit"
-                    ]
-                }
             }
         }
     }
diff --git a/pulse.py b/pulse.py
index b00f272c..39de225f 100755
--- a/pulse.py
+++ b/pulse.py
@@ -208,9 +208,14 @@ def on_build(self, data):
             data['tree'] = 'project'
 
         # Queue up jobs for the branch as given by config settings
-        target_branch = self.config['testrun']['by_branch'][data['tree']]
+        target_branch = self.config['testrun']['by_branch'].get(data['tree'])
         target_platform = self.get_platform_identifier(data['platform'])
 
+        # Ensure that the branch is really supported by us
+        if target_branch is None:
+            self.logger.error('Cancel processing of unsupported branch: %s' % data['tree'])
+            return
+
         # Handle blacklist items if present
         if 'blacklist' in target_branch:
             # Cancel processing of the build if the locale is blacklisted