--- a/mozilla/release-thunderbird-comm-esr52.py
+++ b/mozilla/release-thunderbird-comm-esr52.py
@@ -21,17 +21,17 @@ releaseConfig['productName']         = '
 releaseConfig['stage_product']       = 'thunderbird'
 releaseConfig['appName']             = 'mail'
 releaseConfig['relbranchPrefix']     = 'THUNDERBIRD'
 releaseConfig['mozilla_srcdir']      = 'mozilla'
 #  Current version info
 releaseConfig['version']             = '52.9.1'
 releaseConfig['appVersion']          = '52.9.1'
 releaseConfig['milestone']           = releaseConfig['appVersion']
-releaseConfig['buildNumber']         = 2
+releaseConfig['buildNumber']         = 3
 releaseConfig['baseTag']             = 'THUNDERBIRD_52_9_1'
 releaseConfig['partialUpdates']      = {
 
     '52.7.0': {
         'appVersion': '52.7.0',
         'buildNumber': 1,
         'baseTag': 'THUNDERBIRD_52_7_0',
     },