diff --git a/app/models/user.rb b/app/models/user.rb
index 5b40929..94c3b14 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -22,6 +22,7 @@ class User < ApplicationRecord
   validates_format_of :cn, without: /\A-/,
                            if: Proc.new{ |u| u.cn.present? },
                            message: "is invalid. Usernames need to start with a letter."
+  # FIXME This needs a server restart to apply values
   validates_format_of :cn, without: /\A(#{Setting.reserved_usernames.join('|')})\z/i,
                            message: "has already been taken"