diff --git a/db/migrate/20150729150523_migrate_auto_close_posts.rb b/db/migrate/20150729150523_migrate_auto_close_posts.rb
index 78508d70380..7c6664aa312 100644
--- a/db/migrate/20150729150523_migrate_auto_close_posts.rb
+++ b/db/migrate/20150729150523_migrate_auto_close_posts.rb
@@ -5,7 +5,7 @@ class MigrateAutoClosePosts < ActiveRecord::Migration[4.2]
     I18n.overrides_disabled do
       strings = []
       %w(days hours lastpost_days lastpost_hours lastpost_minutes).map do |k|
-        strings << I18n.t("topic_statuses.autoclosed_enabled_#{k}").values.map { |s| s.sub("%{count}", "\\d+") }
+        strings += I18n.t("topic_statuses.autoclosed_enabled_#{k}").values.map { |s| s.sub("%{count}", "\\d+") }
       end
 
       sql = <<~SQL