What KPIs prove that recovery is stable?

Postmaster metrics:

• Gmail reputation stable at Medium or High for 4+ weeks
• SNDS consistently green
• No yellow or red periods

Engagement metrics:

• Open rates consistent (not declining)
• Click rates stable
• Complaint rate below 0.1%

Delivery metrics:

• Bounce rate stable and low
• No policy bounces
• Consistent inbox placement

Absence of problems:

• No blocklist listings
• No delivery emergencies
• No stakeholder complaints
• Stability means consistent good metrics, not just one good week.
• Health is sustained good vital signs over time, not a single good checkup.