Advanced re-engagement campaigns: edge cases, scale, and monitoring

This guide assumes re-engagement campaigns is already deployed and passing. It covers what breaks at scale and how mature teams operate it.

Edge cases that break a working setup#

• Never sunsetting because list size is a vanity metric.
• Using 'We miss you' subject lines that read as spam.
• Mail forwarded through mailing lists or personal forwarders, which alters headers and content.
• Acquisitions and rebrands that introduce domains nobody audited.
• Vendors silently changing their sending infrastructure.

Operating it as infrastructure#

1. Assign an owner for each sending domain and each vendor relationship.
2. Put DNS records under version control or a change-review process.
3. Alert on authentication pass rate drops and reputation changes, not just outages.
4. Run a quarterly audit against the setup steps below.
5. Document runbooks for the three most common failures.

Reference: the baseline setup#

1. Define inactivity: no clicks or replies in 90 days is a common threshold.
2. Send a 2 to 3 message win-back series with a clear ask to stay subscribed.
3. Suppress anyone who does not engage after the series.
4. Keep a record of suppressed contacts for compliance and future opt-in.

Frequently asked questions#