Are contacts cached when scheduling a mailing?

Question

This might be a stupid question, but I know some poorly designed systems out there, so I just want to make sure.

Scenario

• Monday - Create an Email - Choose a Group/Smart Group - Schedule it to go out Friday
• Though-out the week, you remove members of the group or if a smart group, it updates and removes members of the group. Let's say 10 people are removed.
• Friday email goes out to the group

Do those 10 people that were removed get the email or does it deliver the email to who is in the group when the email is sent?

Answer 1

Thanks to Demerit and Petednz for answering this in the comments.

The answer is that the email is sent to contacts that were in the group(s) when the email was scheduled, not when it actually sends.

This extension, though with flaws addresses the issue. It recalculates the contact groups before sending the email. However it does not work if you do A/B testing or if you use ACL's to restrict who can send emails to what groups. https://github.com/3sd/civicrm-recalculate-recipients

These gitlab issues discuss this in more detail. https://lab.civicrm.org/dev/core/-/issues/2351 and https://lab.civicrm.org/dev/mail/-/issues/45