We send out quite a bit of email via mandrill (as well as SES) and haven't ever experienced this. They should alert you no matter and I am surprised they didn'

We send out quite a bit of email via mandrill (as well as SES) and haven't ever experienced this. They should alert you no matter and I am surprised they didn't. As for mandrill what is your deliverability rate and reputation? We generally maintain just shy of 98% deliverability and an "excellent" reputation on their dashboard. We also follow all the rules for canSPAM even on transactional emails where technically you could get away without some of it. We developed an automated list cleansing system to make sure we keep hard bounces from getting resent, fixes common typos in domains, only retry soft bounces twice for the same campaign etc. The list cleansing helped us go from 95% deliverability and a "Good" reputation up to the 97.5+ and "excellent", which for us helps our clients. Also, another point, you can use sub-accounts to manage higher risk campaigns etc which can help prevent some of the headaches. Not that this solves mandrill not notifying you, but out of curiosity, do you have webhooks setup? We extensively use webhooks to tell us what is happening and while they don't directly tell you sending has been paused (that I know of), the status of the emails in the webhooks would tell you something is wrong. I know for our platform we have a small component we wrote that monitors when email is being sent and expects to see the statuses updated fairly quickly, if it doesn't we get alerted, or if certain percentages of emails start coming back with "bad" statuses as we defined them we get an alert. I would think if you are sending enough email and using any third party email gateway you would want the same thing.