Certification is a measurement exercise, and measurement rewards preparation. Begin the internal count at least twelve months before the ULA term ends.
Inventory every host, cluster and cloud instance where the licensed programs are installed, not merely where they are used. Installation is the trigger under most agreements.
Document virtualisation boundaries carefully. Soft partitioning claims that were never contractually agreed are the single most common source of audit exposure.
Finally, model both outcomes — certify and exit, or renew — with real numbers. Walking into the renewal conversation without your own count means negotiating against someone else's spreadsheet.