Cross-tenant Free/Busy, MailTips, and Calendar Sharing are moving to Cross-Tenant Access Policy

This is a significant change for organizations managing complex Microsoft 365 environments.

Moving cross-tenant Free/Busy, MailTips, and Calendar Sharing into Cross-Tenant Access Policies should provide a more centralized and consistent approach to tenant-to-tenant collaboration.

From a messaging architecture perspective, the key will be understanding the migration path for existing Organization Relationships and how identity, trust, and access policies interact during coexistence.

Definitely something Exchange administrators should start reviewing before it becomes a migration project instead of a configuration change.