[dangrossman]

Mandrill had over $1,000,000/mo in -paying- customers. We got no more time to transition off them than the free users did.

Switching e-mail providers is not something you can do overnight if you send large volumes (large volume does not mean spam: I send purchase receipts, contact forms, notifications, password resets -- transactional mail not ads). Even if you have a team of coders that can drop everything to start integrating alternatives, you need time to warm up your new IP space at a new provider, or your mail ends up in spam folders.

MailChimp screwed a lot of customers, and customers' customers when they gave only 60 days notice.