This morning our sendgrid account (with 4 years of good standing paying $x,000 a year) is showing as suspended. No change in spam or bounce rates (both tiny). No communication from them.
Their support page is showing as 'email only' due to 'volume'.
We have customers with events today that are severely impacted by this. I hate to use HN as a support channel but they don't provide a lot of choices.
I'm afraid HN can't help on that.
But it does recall me a concern we had when we moved our email service to SendGrid. If there's something wrong with the third party, we're doomed... :/
Fortunately their support was able to get back within a couple of hours (much faster than the 3-5 days listed on the page) and reactivated the account.
Looks like a mis-fire of the automated suspension system which seems to be a huge problem of these types of systems when you are on the receiving end.