I have imported all subscribers from another plugin into newsletter. Old plugin didn't have a column can map to list. What I want is creating a new column , call list_num, there will be value from 1-10. When I want to send newsletter, I can choose send to 1 or 2 or 3... in list_num. But apparently I can only choose send newsletter to one of the lists( where the newsletter plugin had defined) or sex. Can I send emails/newsletter base on a extra field where I have defined?