We've fixed a problem with line up/down SMS/email/tweet notifications. This may result in customers receiving old notifications, so please disregard any such historical notifications that you receive.
It looks like the notification system is still a bit broken, with some customers receiving many duplicate notices. We've disabled notifications entirely until we've fixed this. Sorry for any inconvenience.
The notification problem should be fixed now, but please do let support know if you receive any erroneous updates.