20260415 Clarify immutability for LTR backups in Azure SQL

Updated notes on configuring long-term retention backups for Azure SQL Database and Azure SQL Managed Instance, clarifying immutability features.

Author: WilliamDAssafMSFT

azure-sql/database/long-term-retention-overview.md

@@ -28,10 +28,8 @@ Many applications have regulatory, compliance, or other business reasons that re
 By using the LTR feature, you can store specified full SQL Database and SQL Managed Instance backups in redundant Azure Blob storage with a configurable retention policy of up to 10 years. LTR backups can then be restored as a new database. If an LTR policy is configured, automated backups are copied to different blobs for long-term storage which you can then use to restore your database to a specific point in time. The copy process is a background job that has no performance impact on the database workload. The LTR policy for each database can also specify how frequently the LTR backups are created. 
 
 > [!NOTE]  
-> You can [configure long-term retention backups of Azure SQL Database as immutable](backup-immutability.md), a feature currently in preview.
-> 
-> It's not currently possible to configure backups of Azure SQL Managed Instance as [immutable](/azure/storage/blobs/immutable-storage-overview). LTR backups are nonmodifiable, but you can delete them through Azure portal, Azure CLI, PowerShell, or REST API. As a workaround in Azure SQL Managed Instance, you can take [copy-only database backups](/sql/relational-databases/backup-restore/copy-only-backups-sql-server?view=azuresqldb-mi-current&preserve-view=true) and retain them in your own Azure Storage account as an immutable file.
-
+> - In Azure SQL Database, you can [configure long-term retention backups as immutable](backup-immutability.md).
+> - In Azure SQL Managed Instance, it's not currently possible to configure backups as [immutable](/azure/storage/blobs/immutable-storage-overview). LTR backups are nonmodifiable, but you can delete them through Azure portal, Azure CLI, PowerShell, or REST API. As a workaround in Azure SQL Managed Instance, you can take [copy-only database backups](/sql/relational-databases/backup-restore/copy-only-backups-sql-server?view=azuresqldb-mi-current&preserve-view=true) and retain them in your own Azure Storage account as an immutable file.
 
 To enable LTR, you can define a policy using a combination of four parameters: weekly backup retention (W), monthly backup retention (M), yearly backup retention (Y), and week of the year (WeekOfYear). If you specify W, one backup every week is copied to long-term storage. If you specify M, the first backup of each month is copied to the long-term storage. If you specify Y, one backup during the week specified by WeekOfYear is copied to the long-term storage. If the specified WeekOfYear is in the past when the policy is configured, the first LTR backup is created the following year. Each backup is kept in long-term storage according to the policy parameters that are configured when the LTR backup is created.