1. SaaS with generic cloud PTR
Who: A B2B app sending transactional mail from a cloud VM.
Task: Remove static-…hosting… PTR before the November window.
Steps: Select generic PTR + bad/ok HELO as applicable; open ticket with cloud provider for branded PTR; publish A record; verify with official checker.
Result: Warn path with generic PTR badge. Failure avoided: assuming “we have a PTR” equals FCrDNS.
2. ESP multi-tenant pool
Who: ESP platform ops.
Task: Align HELO/PTR branding and separate streams.
Steps: Role=ESP; inventory customer vs platform hostnames; apply ESP large-sender identity guidance alongside this checklist.
Result: ESP-specific checklist lines. Failure avoided: rotating HELO per connection looking like compromise.
3. Dual-stack sender enabling IPv6
Who: University mail team turning up IPv6 SMTP.
Task: Meet IPv6 allocation/rDNS expectations before advertising AAAA MX paths.
Steps: v6=yes; confirm /64-scale planning and reverse DNS; still keep IPv4 FCrDNS healthy.
Result: IPv6 extra checks badge. Failure avoided: IPv6 send without rDNS looking abusive.
Shared closing note: Treat each scenario as a rehearsal for release week. Copy the checklist path into your ticket, assign an owner for every checkbox, and re-read the live official page the morning you ship. Static text here can lag issuer or regulator wording.