A customer was flooding that mx server and delaying mail for other users. We did not notice it right away, as you pointed out.
Sending us automated emails will most likely just give you a bad reputation with our support team. If that is your intention then feel free to do so, but if you really just want to help us improve our service there are better ways to do so.
Please do notify us if you believe there is a problem on our end. Setting a support message to high priority does get noticed, but remember that some problems just take time to resolve. We do not typically respond to messages until the problem is resolved so a long wait for a response does not mean we have not seen the message at all.
This problem should have been resolved much quicker than it was and I do apologize for that. We may have to start restricting the use of our mail servers more to prevent issues like this from happening.