Way to only queue particular emails?

Hi. Really like the plugin, thanks. Is there a way that I can only set a function / hook to let the plugin only queue certain emails? For instance perhaps only emails beginning with a certain subject line, or custom email headers added? I’m using wp_mail() as a custom function to send out a large set of emails, so I can customise it if necessary to hook in to your queue. Then the system can ignore all other standard emails to be sent straight away as normal avoiding the queue.

Hope that’s possible or that you can lead me along the right lines. Thanks.