caveat for us gov regions: double encryption

Author: b-ahibbard

articles/azure-netapp-files/azure-government.md

@@ -26,7 +26,6 @@ All [Azure NetApp Files features](whats-new.md) available on Azure public cloud
 |:--- |:--- |:--- |
 | Azure NetApp Files backup | Generally available (GA) | No |
 | Azure NetApp Files customer-managed keys | Generally available (GA) | No | 
-| Azure NetApp Files double encryption at rest | Public preview | Public preview |
 | Azure NetApp Files large volumes | Generally available (GA) | Generally available [(select regions)](large-volumes-requirements-considerations.md#supported-regions) |
 
 ## Portal access

articles/azure-netapp-files/double-encryption-at-rest.md

@@ -61,14 +61,16 @@ Azure NetApp Files double encryption at rest is supported for the following regi
 * UAE North
 * UK South 
 * UK West
-* US Gov Arizona
-* US Gov Texas
-* US Gov Virginia
+* US Gov Arizona*
+* US Gov Texas*
+* US Gov Virginia*
 * West Europe
 * West US
 * West US 2
 * West US 3
 
+\* Double-encryption at rest in US Gov regions is only supported with platform-managed keys, not customer-managed keys.
+
 ## Considerations
 
 * Azure NetApp Files double encryption at rest supports [Standard network features](azure-netapp-files-network-topologies.md#configurable-network-features), but not Basic network features.