Hello @JohnY70 ,
The Resend option that allows you to select the same or other lists would be your best option. The system will target only contacts that haven't already been sent the email, in the selected list(s).
Additionally, if you need to send an email to a single contact that's already been sent, or a small group of them, you can perform a Quicksend. Quicksends are available through the contacts dashboard, or through emails' reporting pages (for example going into the bounce list, selecting the handful of contacts no longer suspended, Actions > Quicksend > the name of the email you wish to send them). Please be aware that there's a max of 5000 contacts that can be quicksent to at a time.
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