diff --git a/src/System.Numerics.Vectors/ref/Configurations.props b/src/System.Numerics.Vectors/ref/Configurations.props
index 8164b3b7aa54..322defb70701 100644
--- a/src/System.Numerics.Vectors/ref/Configurations.props
+++ b/src/System.Numerics.Vectors/ref/Configurations.props
@@ -9,7 +9,6 @@
     <BuildConfigurations>
       netcoreapp;
       uap;
-      uapaot;
       netfx;
       $(PackageConfigurations);
     </BuildConfigurations>
diff --git a/src/System.Threading.Thread/src/System.Threading.Thread.csproj b/src/System.Threading.Thread/src/System.Threading.Thread.csproj
index 8d797e1c6f5a..d2e3db5937e9 100644
--- a/src/System.Threading.Thread/src/System.Threading.Thread.csproj
+++ b/src/System.Threading.Thread/src/System.Threading.Thread.csproj
@@ -6,7 +6,6 @@
     <OutputType>Library</OutputType>
     <IsPartialFacadeAssembly>true</IsPartialFacadeAssembly>
     <ProjectGuid>{06197EED-FF48-43F3-976D-463839D43E8C}</ProjectGuid>
-    <DefineConstants Condition="'$(TargetGroup)' == 'uapaot'">$(DefineConstants);uapaot</DefineConstants>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'netcoreapp-Unix-Debug|AnyCPU'" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'netcoreapp-Unix-Release|AnyCPU'" />
diff --git a/src/System.Threading.Thread/src/System/Threading/Thread.cs b/src/System.Threading.Thread/src/System/Threading/Thread.cs
index cf62d475a28a..c504b7c7d602 100644
--- a/src/System.Threading.Thread/src/System/Threading/Thread.cs
+++ b/src/System.Threading.Thread/src/System/Threading/Thread.cs
@@ -272,15 +272,7 @@ public void SetCompressedStack(CompressedStack stack)
             throw new InvalidOperationException(SR.Thread_GetSetCompressedStack_NotSupported);
         }
 
-#if uapaot
-        //
-        // Todo: Remove when we update System.Private.CoreLib for uapaot
-        // https://github.com/dotnet/corefx/issues/27619
-        //
-        public static int GetCurrentProcessorId() => 0;
-#else
         public static int GetCurrentProcessorId() => RuntimeThread.GetCurrentProcessorId();
-#endif
         public static AppDomain GetDomain() => AppDomain.CurrentDomain;
         public static int GetDomainID() => GetDomain().Id;
         public override int GetHashCode() => ManagedThreadId;