I think I'm getting there.
I created a CRON for both the Mailer Automation Settings and also in the main Settings -> Automation Settings for Mass Expiry Settings. They'll run once each morning.
Where I'm a little confused is how I can set the Main Mailer Triggering Conditions to trigger for a wide variety of Subscription Dates - They range from 1/15/2012 (expired) to 7/11/2018 (still active).
Obviously, no Active subscription needs to get the email - just those which have expired (which is about 82 records as of today).
How do I set the trigger so it will go out to all the records I import that are expired?
Thank you,
Ernie