10 months?? Nahh it's too long to wait. In my case I have 2 companies to manage. I cannot wait so long.. Need better ways to promote and generate visitors and sales.You can do this with just a few gmails accounts and a lot of time. Write a simple python script to send emails from Gmail, then send 5-10 emails per day using the script, a few hours apart, and eventually work your way up to 50 emails per day. You'll get through the list of 20,000 in about 10 months. If you don't want to end up in spam, this is probably the best way. If you have access to multiple gmails on different IPs, you can significantly speed up the time it takes you to get through the list.
But thanks anyway.