Thanks for this wonderful plugin!
I'd like to send out my emails asynchronously, but it seems that this option falls out of the $message variable that can be modified with mandrill_payload. Could a filter for this be added to the plugin? Currently there's no other way than to modify the code.
The reason I'd like to send them asynchronously is because I'd like to send out 50 emails or so at once, but it would take too long to do that. Ideally I'd like to make just one request, but I don't think that's currently possible? I don't want to send one message to multiple recipients, I'd like the send out a unique message to each. This is useful when you're providing links to unsubscribe.
Thanks a lot!