diff --git a/Microsoft.Azure.Cosmos/Directory.Build.props b/Microsoft.Azure.Cosmos/Directory.Build.props
index 56600d74e7..31516a6fcd 100644
--- a/Microsoft.Azure.Cosmos/Directory.Build.props
+++ b/Microsoft.Azure.Cosmos/Directory.Build.props
@@ -3,7 +3,7 @@
   <PropertyGroup>
     <ClientOfficialVersion>3.9.1</ClientOfficialVersion>
     <ClientPreviewVersion>3.9.1</ClientPreviewVersion>
-    <DirectVersion>3.9.0</DirectVersion>
+    <DirectVersion>3.10.0</DirectVersion>
     <EncryptionVersion>1.0.0-preview4</EncryptionVersion>
     <HybridRowVersion>1.0.0-preview</HybridRowVersion>
     <AboveDirBuildProps>$([MSBuild]::GetPathOfFileAbove('Directory.Build.props', '$(MSBuildThisFileDirectory)../'))</AboveDirBuildProps>
diff --git a/Microsoft.Azure.Cosmos/src/Diagnostics/CosmosDiagnosticsSerializerVisitor.cs b/Microsoft.Azure.Cosmos/src/Diagnostics/CosmosDiagnosticsSerializerVisitor.cs
index b287d4ea1e..ca684c3991 100644
--- a/Microsoft.Azure.Cosmos/src/Diagnostics/CosmosDiagnosticsSerializerVisitor.cs
+++ b/Microsoft.Azure.Cosmos/src/Diagnostics/CosmosDiagnosticsSerializerVisitor.cs
@@ -228,6 +228,9 @@ public override void Visit(StoreResponseStatistics storeResponseStatistics)
 
             if (storeResponseStatistics.StoreResult != null)
             {
+                this.jsonWriter.WritePropertyName("ActivityId");
+                this.jsonWriter.WriteValue(storeResponseStatistics.StoreResult.ActivityId);
+
                 this.jsonWriter.WritePropertyName("StoreResult");
                 this.jsonWriter.WriteValue(storeResponseStatistics.StoreResult.ToString());
             }
diff --git a/Microsoft.Azure.Cosmos/src/Regions.cs b/Microsoft.Azure.Cosmos/src/Regions.cs
index c429bd47f5..175ed29d6e 100644
--- a/Microsoft.Azure.Cosmos/src/Regions.cs
+++ b/Microsoft.Azure.Cosmos/src/Regions.cs
@@ -294,5 +294,10 @@ public static class Regions
         /// Name of the Azure Norway West region in the Azure Cosmos DB service.
         /// </summary>
         public const string NorwayWest = "Norway West";
+
+        /// <summary>
+        /// Name of the Azure Brazil Southeast region in the Azure Cosmos DB service.
+        /// </summary>
+        public const string BrazilSoutheast = "Brazil Southeast";
     }
 }
diff --git a/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.EmulatorTests/TransportWrapperTests.cs b/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.EmulatorTests/TransportWrapperTests.cs
index 13ae0c87be..6ed58787fa 100644
--- a/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.EmulatorTests/TransportWrapperTests.cs
+++ b/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.EmulatorTests/TransportWrapperTests.cs
@@ -193,7 +193,8 @@ private static void ThrowTransportExceptionOnItemOperation(
                     numberOfReadRegions: 1,
                     itemLSN: 5,
                     sessionToken: null,
-                    usingLocalLSN: true));
+                    usingLocalLSN: true,
+                    activityId: Guid.NewGuid().ToString()));
 
                 throw Documents.Rntbd.TransportExceptions.GetServiceUnavailableException(physicalAddress, Guid.NewGuid(),
                     transportException);
diff --git a/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/CosmosDiagnosticsUnitTests.cs b/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/CosmosDiagnosticsUnitTests.cs
index 6256494325..8b2c06c670 100644
--- a/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/CosmosDiagnosticsUnitTests.cs
+++ b/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/CosmosDiagnosticsUnitTests.cs
@@ -163,7 +163,8 @@ public void ValidateClientSideRequestStatisticsToString()
                     numberOfReadRegions: 1,
                     itemLSN: 5,
                     sessionToken: null,
-                    usingLocalLSN: true));
+                    usingLocalLSN: true,
+                    activityId: Guid.NewGuid().ToString()));
 
             string statistics = clientSideRequestStatistics.ToString();
             Assert.AreEqual("Please see CosmosDiagnostics", statistics);
diff --git a/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/DotNetSDKAPI.json b/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/DotNetSDKAPI.json
index 8845985ed0..4ef2b50f08 100644
--- a/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/DotNetSDKAPI.json
+++ b/Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/DotNetSDKAPI.json
@@ -4433,6 +4433,11 @@
           "Attributes": [],
           "MethodInfo": null
         },
+        "System.String BrazilSoutheast": {
+          "Type": "Field",
+          "Attributes": [],
+          "MethodInfo": null
+        },
         "System.String CanadaCentral": {
           "Type": "Field",
           "Attributes": [],
diff --git a/changelog.md b/changelog.md
index 076898cbf4..b524ce8769 100644
--- a/changelog.md
+++ b/changelog.md
@@ -7,8 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- [#1578](https://github.com/Azure/azure-cosmos-dotnet-v3/pull/1578) Query: Add optimization to access the stream buffer
+
 ### Fixed
 
+- [#1578](https://github.com/Azure/azure-cosmos-dotnet-v3/pull/1578) ApplicationRegion: Fix ApplicationRegion to ensure the correct order is being used for failover scenarios
+
 ## <a name="3.9.1"/> [3.9.1](https://www.nuget.org/packages/Microsoft.Azure.Cosmos/3.9.1) - 2020-05-19
 ## <a name="3.9.1-preview"/> [3.9.1-preview](https://www.nuget.org/packages/Microsoft.Azure.Cosmos/3.9.1-preview) - 2020-05-19