pyramid_mailer send_to_queue() - pyramid

Question

So I have configured my pyramid application to send all mails to a mailqueue, this was no problem.
I created the maildir as such:
mkdir -p /home/luke/Maildir/{cur,new,tmp}
Now, I send my mail to the queue, and check the contents of:
/home/luke/Maildir/new
And there are all my emails waiting to send. So I run the qp command as per the docs, first of with the options as specified:
qp --hostname example.com --port 587 --username user#example.com --password etcR8hP6xMGqSU-adfaf --force-tls ~/Maildr/
These details are what I am using to connect with mandrill, note that my local postfix server is also configured to send mail via mandrill, which works fine and I can run the sendmail command and send mail.
So I also tried sending with the config in an .ini file
qp --config ~/python/delivery-2.0/mail.ini ~/Maildr/
With my mail.ini looking like this:
[app:qp]
hostname = smtp.mandrillapp.com
host = smtp.mandrillapp.com
port = 587
username = user#example.com
password = etcR8hP6xMGqSU-adfaf
tls = True
These are the same settings that work inside my production.ini file that pyramid mailer uses for message.send() where the pyramid_mailer sends the message instantly, this works fine.
When I run the qp command I get no errors, but no messages send. The documentation on QP is very limited, so I am hopeful that someone on here can help, thanks!