Microsoft Entra: Enhanced Security Accounts Manager (sAM) Account Name support for Microsoft Entra Domain Services
Enhanced sAMAccountName synchronization is now available in public preview for Microsoft Entra Domain Services. Existing managed domains can opt into the new behavior while new domains get it by default; hybrid users will be updated during sync and cloud-only users without onPremisesSamAccountName will continue using mailNickname-based generation.
Microsoft's description
Enhanced support for synchronizing the Security Accounts Manager account name (sAMAccountName) with Microsoft Entra Domain Services is now in Public Preview. This feature allows sAMAccountName to be populated from the onPremisesSamAccountName attribute in Microsoft Entra ID. Existing managed domains can enable the new synchronization behavior, while it is enabled by default for new managed domains. When enabled, existing hybrid users are updated during synchronization; cloud-only users without an onPremisesSamAccountName value continue to use mailNickname-based generation. The feature is available for Enterprise and Premium SKUs.