diff --git a/src/Build.UnitTests/WarningsAsMessagesAndErrors_Tests.cs b/src/Build.UnitTests/WarningsAsMessagesAndErrors_Tests.cs
index 6041fbc45ac..7341d6f913d 100644
--- a/src/Build.UnitTests/WarningsAsMessagesAndErrors_Tests.cs
+++ b/src/Build.UnitTests/WarningsAsMessagesAndErrors_Tests.cs
@@ -9,6 +9,7 @@
 using Shouldly;
 using Xunit;
 using Xunit.Abstractions;
+using static System.Net.WebRequestMethods;
 
 #nullable disable
 
@@ -35,7 +36,7 @@ public void TreatAllWarningsAsErrors()
             ObjectModelHelpers.BuildProjectExpectSuccess(GetTestProject(treatAllWarningsAsErrors: false));
         }
 
-        [Fact]
+        [Fact (Skip = "TreatWarningAsErrors is excluded in the first wave of the unification. See https://github.com/dotnet/msbuild/issues/10871")]
         public void TreatAllWarningsAsErrorsNoPrefix()
         {
             MockLogger logger = ObjectModelHelpers.BuildProjectExpectFailure(GetTestProject(customProperties: new Dictionary<string, string>
@@ -354,9 +355,10 @@ private string GetTestProject(bool? treatAllWarningsAsErrors = null, string warn
         [InlineData("MSB1235", "MSB1234", "MSB1234", "MSB1234", false)] // Log MSB1234, treat as error via MSBuildWarningsAsErrors
         [InlineData("MSB1235", "", "MSB1234", "MSB1234", true)] // Log MSB1234, expect MSB1234 as error via MSBuildTreatWarningsAsErrors
         [InlineData("MSB1234", "MSB1234", "MSB1234", "MSB4181", true)]// Log MSB1234, MSBuildWarningsAsMessages takes priority
-        [InlineData("MSB1235", "MSB1234", "MSB1234", "MSB1234", false, false)] // Log MSB1234, treat as error via BuildWarningsAsErrors
-        [InlineData("MSB1235", "", "MSB1234", "MSB1234", true, false)] // Log MSB1234, expect MSB1234 as error via BuildTreatWarningsAsErrors
-        [InlineData("MSB1234", "MSB1234", "MSB1234", "MSB4181", true, false)]// Log MSB1234, BuildWarningsAsMessages takes priority
+        // TreatWarningAsErrors is excluded in the first wave of the unification.See https://github.com/dotnet/msbuild/issues/10871
+        // [InlineData("MSB1235", "MSB1234", "MSB1234", "MSB1234", false, false)] // Log MSB1234, treat as error via BuildWarningsAsErrors
+        // [InlineData("MSB1235", "", "MSB1234", "MSB1234", true, false)] // Log MSB1234, expect MSB1234 as error via BuildTreatWarningsAsErrors
+        // [InlineData("MSB1234", "MSB1234", "MSB1234", "MSB4181", true, false)]// Log MSB1234, BuildWarningsAsMessages takes priority
         public void WarningsAsErrorsAndMessages_Tests(string WarningsAsMessages,
                                                       string WarningsAsErrors,
                                                       string WarningToLog,
@@ -529,8 +531,9 @@ public void TaskLogsWarningAsError_BatchedBuild()
         [Theory]
         [InlineData("MSB1234", false, 1, 1)]
         [InlineData("MSB0000", true, 0, 2)]
-        [InlineData("MSB1234", false, 1, 1, false)]
-        [InlineData("MSB0000", true, 0, 2, false)]
+        // TreatWarningAsErrors is excluded in the first wave of the unification.See https://github.com/dotnet/msbuild/issues/10871
+        // [InlineData("MSB1234", false, 1, 1, false)  
+        // [InlineData("MSB0000", true, 0, 2, false)
         public void TaskReturnsTrue_Tests(string warningsAsErrors, bool treatAllWarningsAsErrors, int warningCountShouldBe, int errorCountShouldBe, bool useMSPrefix = true)
         {
             string prefix = useMSPrefix ? "MSBuild" : "";
diff --git a/src/Build/BackEnd/Components/RequestBuilder/RequestBuilder.cs b/src/Build/BackEnd/Components/RequestBuilder/RequestBuilder.cs
index a5b8e6b9717..6126bdd8155 100644
--- a/src/Build/BackEnd/Components/RequestBuilder/RequestBuilder.cs
+++ b/src/Build/BackEnd/Components/RequestBuilder/RequestBuilder.cs
@@ -1390,9 +1390,7 @@ private void ConfigureWarningsAsErrorsAndMessages()
             // Ensure everything that is required is available at this time
             if (project != null && buildEventContext != null && loggingService != null && buildEventContext.ProjectInstanceId != BuildEventContext.InvalidProjectInstanceId)
             {
-                if (String.Equals(project.GetEngineRequiredPropertyValue(MSBuildConstants.MSBuildPrefix + MSBuildConstants.TreatWarningsAsErrors)?.Trim(), "true", StringComparison.OrdinalIgnoreCase) ||
-                    (String.Equals(project.GetEngineRequiredPropertyValue(MSBuildConstants.TreatWarningsAsErrors)?.Trim(), "true", StringComparison.OrdinalIgnoreCase) &&
-                     ChangeWaves.AreFeaturesEnabled(ChangeWaves.Wave17_14)))
+                if (String.Equals(project.GetEngineRequiredPropertyValue(MSBuildConstants.MSBuildPrefix + MSBuildConstants.TreatWarningsAsErrors)?.Trim(), "true", StringComparison.OrdinalIgnoreCase))
                 {
                     // If <MSBuildTreatWarningsAsErrors was specified then an empty ISet<string> signals the IEventSourceSink to treat all warnings as errors
                     loggingService.AddWarningsAsErrors(buildEventContext, new HashSet<string>());
diff --git a/src/UnitTests.Shared/ObjectModelHelpers.cs b/src/UnitTests.Shared/ObjectModelHelpers.cs
index 887d54bf7f0..9ad6e7fc90d 100644
--- a/src/UnitTests.Shared/ObjectModelHelpers.cs
+++ b/src/UnitTests.Shared/ObjectModelHelpers.cs
@@ -782,8 +782,13 @@ public static void BuildProjectExpectSuccess(
         /// expected to fail.
         /// </summary>
         /// <param name="projectContents">The project file content in string format.</param>
+        ///  <param name="testOutputHelper"><see cref="ITestOutputHelper"/> to log to.</param>
+        /// <param name="loggerVerbosity">The required logging verbosity.</param>
         /// <returns>The <see cref="MockLogger"/> that was used during evaluation and build.</returns>
-        public static MockLogger BuildProjectExpectFailure([StringSyntax(StringSyntaxAttribute.Xml)] string projectContents)
+        public static MockLogger BuildProjectExpectFailure(
+            [StringSyntax(StringSyntaxAttribute.Xml)] string projectContents,
+            ITestOutputHelper testOutputHelper = null,
+            LoggerVerbosity loggerVerbosity = LoggerVerbosity.Normal)
         {
             MockLogger logger = new MockLogger(testOutputHelper);
             BuildProjectExpectFailure(projectContents, logger);