diff --git a/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IBinaryOperatorExpression.cs b/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IBinaryOperatorExpression.cs
index dafeda5eb8912..8a3e120b593ab 100644
--- a/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IBinaryOperatorExpression.cs
+++ b/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IBinaryOperatorExpression.cs
@@ -7937,7 +7937,7 @@ void M(int arg)
       Operand: 
         ILiteralOperation (OperationKind.Literal, Type: System.Int32, Constant: 0) (Syntax: '0')
   RightOperand: 
-    IFromEndIndexOperation (OperationKind.FromEndIndex, Type: System.Index) (Syntax: '^1')
+    IFromEndIndexOperation (OperationKind.None, Type: System.Index) (Syntax: '^1')
       Operand: 
         ILiteralOperation (OperationKind.Literal, Type: System.Int32, Constant: 1) (Syntax: '1')
 ";
@@ -8079,7 +8079,7 @@ void M(int? start, int? end)
       Operand: 
         IParameterReferenceOperation: start (OperationKind.ParameterReference, Type: System.Int32?) (Syntax: 'start')
   RightOperand: 
-    IFromEndIndexOperation (IsLifted) (OperationKind.FromEndIndex, Type: System.Index?) (Syntax: '^end')
+    IFromEndIndexOperation (IsLifted) (OperationKind.None, Type: System.Index?) (Syntax: '^end')
       Operand: 
         IParameterReferenceOperation: end (OperationKind.ParameterReference, Type: System.Int32?) (Syntax: 'end')
 ";
diff --git a/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IFromEndIndexOperation_IRangeOperation.cs b/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IFromEndIndexOperation_IRangeOperation.cs
index bf02685e21dfe..c4e16d2743c6d 100644
--- a/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IFromEndIndexOperation_IRangeOperation.cs
+++ b/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IFromEndIndexOperation_IRangeOperation.cs
@@ -34,7 +34,7 @@ void M(int arg)
           IVariableDeclaratorOperation (Symbol: System.Index x) (OperationKind.VariableDeclarator, Type: null) (Syntax: 'x = ^arg')
             Initializer: 
               IVariableInitializerOperation (OperationKind.VariableInitializer, Type: null) (Syntax: '= ^arg')
-                IFromEndIndexOperation (OperationKind.FromEndIndex, Type: System.Index) (Syntax: '^arg')
+                IFromEndIndexOperation (OperationKind.None, Type: System.Index) (Syntax: '^arg')
                   Operand: 
                     IParameterReferenceOperation: arg (OperationKind.ParameterReference, Type: System.Int32) (Syntax: 'arg')
       Initializer: 
@@ -60,7 +60,7 @@ void M(int arg)
               Left: 
                 ILocalReferenceOperation: x (IsDeclaration: True) (OperationKind.LocalReference, Type: System.Index, IsImplicit) (Syntax: 'x = ^arg')
               Right: 
-                IFromEndIndexOperation (OperationKind.FromEndIndex, Type: System.Index) (Syntax: '^arg')
+                IFromEndIndexOperation (OperationKind.None, Type: System.Index) (Syntax: '^arg')
                   Operand: 
                     IParameterReferenceOperation: arg (OperationKind.ParameterReference, Type: System.Int32) (Syntax: 'arg')
 
diff --git a/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IUnaryOperatorExpression.cs b/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IUnaryOperatorExpression.cs
index a4e779c35a3ed..76efa2a88304b 100644
--- a/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IUnaryOperatorExpression.cs
+++ b/src/Compilers/CSharp/Test/IOperation/IOperation/IOperationTests_IUnaryOperatorExpression.cs
@@ -3629,7 +3629,7 @@ void M(int arg)
 }").VerifyDiagnostics();
 
             string expectedOperationTree = @"
-IFromEndIndexOperation (OperationKind.FromEndIndex, Type: System.Index) (Syntax: '^arg')
+IFromEndIndexOperation (OperationKind.None, Type: System.Index) (Syntax: '^arg')
   Operand: 
     IParameterReferenceOperation: arg (OperationKind.ParameterReference, Type: System.Int32) (Syntax: 'arg')
 ";
@@ -3652,7 +3652,7 @@ void M(int? arg)
 }").VerifyDiagnostics();
 
             string expectedOperationTree = @"
-IFromEndIndexOperation (IsLifted) (OperationKind.FromEndIndex, Type: System.Index?) (Syntax: '^arg')
+IFromEndIndexOperation (IsLifted) (OperationKind.None, Type: System.Index?) (Syntax: '^arg')
   Operand: 
     IParameterReferenceOperation: arg (OperationKind.ParameterReference, Type: System.Int32?) (Syntax: 'arg')
 ";
@@ -3675,7 +3675,7 @@ void M(byte arg)
 }").VerifyDiagnostics();
 
             string expectedOperationTree = @"
-IFromEndIndexOperation (OperationKind.FromEndIndex, Type: System.Index) (Syntax: '^arg')
+IFromEndIndexOperation (OperationKind.None, Type: System.Index) (Syntax: '^arg')
   Operand: 
     IConversionOperation (TryCast: False, Unchecked) (OperationKind.Conversion, Type: System.Int32, IsImplicit) (Syntax: 'arg')
       Conversion: CommonConversion (Exists: True, IsIdentity: False, IsNumeric: True, IsReference: False, IsUserDefined: False) (MethodSymbol: null)
diff --git a/src/Compilers/Core/Portable/Operations/ControlFlowGraphBuilder.cs b/src/Compilers/Core/Portable/Operations/ControlFlowGraphBuilder.cs
index 30ca52b09e5a6..4267cef0a9637 100644
--- a/src/Compilers/Core/Portable/Operations/ControlFlowGraphBuilder.cs
+++ b/src/Compilers/Core/Portable/Operations/ControlFlowGraphBuilder.cs
@@ -6567,7 +6567,7 @@ public override IOperation VisitDelegateCreation(IDelegateCreationOperation oper
                 operation.Syntax, operation.Type, operation.ConstantValue, IsImplicit(operation));
         }
 
-        public override IOperation VisitFromEndIndexOperation(IFromEndIndexOperation operation, int? argument)
+        internal override IOperation VisitFromEndIndexOperation(IFromEndIndexOperation operation, int? argument)
         {
             return new FromEndIndexOperation(operation.IsLifted, semanticModel: null, operation.Syntax, operation.Type, Visit(operation.Operand), operation.Symbol, isImplicit: IsImplicit(operation));
         }
diff --git a/src/Compilers/Core/Portable/Operations/IIndexOperation.cs b/src/Compilers/Core/Portable/Operations/IIndexOperation.cs
index 4b6d32bb77e47..c6dd0b8c42515 100644
--- a/src/Compilers/Core/Portable/Operations/IIndexOperation.cs
+++ b/src/Compilers/Core/Portable/Operations/IIndexOperation.cs
@@ -12,7 +12,7 @@ namespace Microsoft.CodeAnalysis.Operations
     /// <remarks>
     /// This interface is reserved for implementation by its associated APIs. We reserve the right to change it in the future.
     /// </remarks>
-    public interface IFromEndIndexOperation : IOperation
+    internal interface IFromEndIndexOperation : IOperation
     {
         /// <summary>
         /// The operand.
diff --git a/src/Compilers/Core/Portable/Operations/OperationCloner.cs b/src/Compilers/Core/Portable/Operations/OperationCloner.cs
index 5a8374af986e7..0f98044ed2b5e 100644
--- a/src/Compilers/Core/Portable/Operations/OperationCloner.cs
+++ b/src/Compilers/Core/Portable/Operations/OperationCloner.cs
@@ -625,7 +625,7 @@ public override IOperation VisitStaticLocalInitializationSemaphore(IStaticLocalI
             throw ExceptionUtilities.Unreachable;
         }
 
-        public override IOperation VisitFromEndIndexOperation(IFromEndIndexOperation operation, object argument)
+        internal override IOperation VisitFromEndIndexOperation(IFromEndIndexOperation operation, object argument)
         {
             return new FromEndIndexOperation(operation.IsLifted, ((Operation)operation).OwningSemanticModel, operation.Syntax, operation.Type, Visit(operation.Operand), operation.Symbol, operation.IsImplicit);
         }
diff --git a/src/Compilers/Core/Portable/Operations/OperationKind.cs b/src/Compilers/Core/Portable/Operations/OperationKind.cs
index f7dbd3839904f..49985ee703719 100644
--- a/src/Compilers/Core/Portable/Operations/OperationKind.cs
+++ b/src/Compilers/Core/Portable/Operations/OperationKind.cs
@@ -227,8 +227,8 @@ public enum OperationKind
 
         /// <summary>Indicates an <see cref="IRangeOperation"/>.</summary>
         Range = 0x63,
-        /// <summary>Indicates an <see cref="IFromEndIndexOperation"/>.</summary>
-        FromEndIndex = 0x64,
+        // Unused, FromEndIndex will be a unary operator: https://github.com/dotnet/roslyn/pull/32918
+        //FromEndIndex = 0x64,
         /// <summary>Indicates an <see cref="IReDimOperation"/>.</summary>
         ReDim = 0x65,
         /// <summary>Indicates an <see cref="IReDimClauseOperation"/>.</summary>
diff --git a/src/Compilers/Core/Portable/Operations/OperationNodes.cs b/src/Compilers/Core/Portable/Operations/OperationNodes.cs
index e3c659211f8ca..0df809fca8432 100644
--- a/src/Compilers/Core/Portable/Operations/OperationNodes.cs
+++ b/src/Compilers/Core/Portable/Operations/OperationNodes.cs
@@ -9401,7 +9401,7 @@ public override IObjectOrCollectionInitializerOperation Initializer
     internal abstract class BaseFromEndIndexOperation : Operation, IFromEndIndexOperation
     {
         protected BaseFromEndIndexOperation(bool isLifted, SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, IMethodSymbol symbol, bool isImplicit) :
-                    base(OperationKind.FromEndIndex, semanticModel, syntax, type, constantValue: default, isImplicit: isImplicit)
+                    base(OperationKind.None, semanticModel, syntax, type, constantValue: default, isImplicit: isImplicit)
         {
             IsLifted = isLifted;
             Symbol = symbol;
diff --git a/src/Compilers/Core/Portable/Operations/OperationVisitor.cs b/src/Compilers/Core/Portable/Operations/OperationVisitor.cs
index e3f992c22d5d5..f82ee037e0822 100644
--- a/src/Compilers/Core/Portable/Operations/OperationVisitor.cs
+++ b/src/Compilers/Core/Portable/Operations/OperationVisitor.cs
@@ -585,7 +585,7 @@ public virtual void VisitStaticLocalInitializationSemaphore(IStaticLocalInitiali
             DefaultVisit(operation);
         }
 
-        public virtual void VisitFromEndIndexOperation(IFromEndIndexOperation operation)
+        internal virtual void VisitFromEndIndexOperation(IFromEndIndexOperation operation)
         {
             DefaultVisit(operation);
         }
@@ -1193,7 +1193,7 @@ public virtual TResult VisitStaticLocalInitializationSemaphore(IStaticLocalIniti
             return DefaultVisit(operation, argument);
         }
 
-        public virtual TResult VisitFromEndIndexOperation(IFromEndIndexOperation operation, TArgument argument)
+        internal virtual TResult VisitFromEndIndexOperation(IFromEndIndexOperation operation, TArgument argument)
         {
             return DefaultVisit(operation, argument);
         }
diff --git a/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt b/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt
index fb166541efc94..0cdb57ec5274e 100644
--- a/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt
+++ b/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt
@@ -5,7 +5,6 @@ Microsoft.CodeAnalysis.ITypeSymbol.IsUnmanagedType.get -> bool
 Microsoft.CodeAnalysis.OperationKind.Binary = 32 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.ConstructorBody = 89 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.DiscardPattern = 104 -> Microsoft.CodeAnalysis.OperationKind
-Microsoft.CodeAnalysis.OperationKind.FromEndIndex = 100 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.MethodBody = 88 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.Range = 99 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.RecursivePattern = 103 -> Microsoft.CodeAnalysis.OperationKind
@@ -168,10 +167,6 @@ Microsoft.CodeAnalysis.Operations.ICoalesceOperation.ValueConversion.get -> Micr
 Microsoft.CodeAnalysis.Operations.IEventAssignmentOperation.EventReference.get -> Microsoft.CodeAnalysis.IOperation
 Microsoft.CodeAnalysis.Operations.IForLoopOperation.ConditionLocals.get -> System.Collections.Immutable.ImmutableArray<Microsoft.CodeAnalysis.ILocalSymbol>
 Microsoft.CodeAnalysis.Operations.IForToLoopOperation.IsChecked.get -> bool
-Microsoft.CodeAnalysis.Operations.IFromEndIndexOperation
-Microsoft.CodeAnalysis.Operations.IFromEndIndexOperation.IsLifted.get -> bool
-Microsoft.CodeAnalysis.Operations.IFromEndIndexOperation.Operand.get -> Microsoft.CodeAnalysis.IOperation
-Microsoft.CodeAnalysis.Operations.IFromEndIndexOperation.Symbol.get -> Microsoft.CodeAnalysis.IMethodSymbol
 Microsoft.CodeAnalysis.Operations.IInstanceReferenceOperation.ReferenceKind.get -> Microsoft.CodeAnalysis.Operations.InstanceReferenceKind
 Microsoft.CodeAnalysis.Operations.ILoopOperation.ContinueLabel.get -> Microsoft.CodeAnalysis.ILabelSymbol
 Microsoft.CodeAnalysis.Operations.ILoopOperation.ExitLabel.get -> Microsoft.CodeAnalysis.ILabelSymbol
@@ -213,7 +208,6 @@ virtual Microsoft.CodeAnalysis.Operations.OperationVisitor.VisitDiscardPattern(M
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor.VisitFlowAnonymousFunction(Microsoft.CodeAnalysis.FlowAnalysis.IFlowAnonymousFunctionOperation operation) -> void
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor.VisitFlowCapture(Microsoft.CodeAnalysis.FlowAnalysis.IFlowCaptureOperation operation) -> void
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor.VisitFlowCaptureReference(Microsoft.CodeAnalysis.FlowAnalysis.IFlowCaptureReferenceOperation operation) -> void
-virtual Microsoft.CodeAnalysis.Operations.OperationVisitor.VisitFromEndIndexOperation(Microsoft.CodeAnalysis.Operations.IFromEndIndexOperation operation) -> void
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor.VisitIsNull(Microsoft.CodeAnalysis.FlowAnalysis.IIsNullOperation operation) -> void
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor.VisitRangeOperation(Microsoft.CodeAnalysis.Operations.IRangeOperation operation) -> void
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor.VisitReDim(Microsoft.CodeAnalysis.Operations.IReDimOperation operation) -> void
@@ -228,7 +222,6 @@ virtual Microsoft.CodeAnalysis.Operations.OperationVisitor<TArgument, TResult>.V
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor<TArgument, TResult>.VisitFlowAnonymousFunction(Microsoft.CodeAnalysis.FlowAnalysis.IFlowAnonymousFunctionOperation operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor<TArgument, TResult>.VisitFlowCapture(Microsoft.CodeAnalysis.FlowAnalysis.IFlowCaptureOperation operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor<TArgument, TResult>.VisitFlowCaptureReference(Microsoft.CodeAnalysis.FlowAnalysis.IFlowCaptureReferenceOperation operation, TArgument argument) -> TResult
-virtual Microsoft.CodeAnalysis.Operations.OperationVisitor<TArgument, TResult>.VisitFromEndIndexOperation(Microsoft.CodeAnalysis.Operations.IFromEndIndexOperation operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor<TArgument, TResult>.VisitIsNull(Microsoft.CodeAnalysis.FlowAnalysis.IIsNullOperation operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor<TArgument, TResult>.VisitRangeOperation(Microsoft.CodeAnalysis.Operations.IRangeOperation operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Operations.OperationVisitor<TArgument, TResult>.VisitReDim(Microsoft.CodeAnalysis.Operations.IReDimOperation operation, TArgument argument) -> TResult
diff --git a/src/Test/Utilities/Portable/Compilation/ControlFlowGraphVerifier.cs b/src/Test/Utilities/Portable/Compilation/ControlFlowGraphVerifier.cs
index 880b31ecc1a7b..9c27c687b91fc 100644
--- a/src/Test/Utilities/Portable/Compilation/ControlFlowGraphVerifier.cs
+++ b/src/Test/Utilities/Portable/Compilation/ControlFlowGraphVerifier.cs
@@ -1800,7 +1800,6 @@ propertyReference.Parent is ISimpleAssignmentOperation simpleAssignment &&
                 case OperationKind.Discard:
                 case OperationKind.ReDim:
                 case OperationKind.ReDimClause:
-                case OperationKind.FromEndIndex:
                 case OperationKind.Range:
                 case OperationKind.RecursivePattern:
                 case OperationKind.DiscardPattern:
diff --git a/src/Test/Utilities/Portable/Compilation/OperationTreeVerifier.cs b/src/Test/Utilities/Portable/Compilation/OperationTreeVerifier.cs
index c6d42196b6cd1..7f3953dd2c407 100644
--- a/src/Test/Utilities/Portable/Compilation/OperationTreeVerifier.cs
+++ b/src/Test/Utilities/Portable/Compilation/OperationTreeVerifier.cs
@@ -1878,7 +1878,7 @@ public override void VisitStaticLocalInitializationSemaphore(IStaticLocalInitial
             LogCommonPropertiesAndNewLine(operation);
         }
 
-        public override void VisitFromEndIndexOperation(IFromEndIndexOperation operation)
+        internal override void VisitFromEndIndexOperation(IFromEndIndexOperation operation)
         {
             LogString(nameof(IFromEndIndexOperation));
 
diff --git a/src/Test/Utilities/Portable/Compilation/TestOperationVisitor.cs b/src/Test/Utilities/Portable/Compilation/TestOperationVisitor.cs
index 29767a450c1be..0f9aa18d5e015 100644
--- a/src/Test/Utilities/Portable/Compilation/TestOperationVisitor.cs
+++ b/src/Test/Utilities/Portable/Compilation/TestOperationVisitor.cs
@@ -1421,9 +1421,9 @@ public override void VisitStaticLocalInitializationSemaphore(IStaticLocalInitial
             Assert.True(operation.Local.IsStatic);
         }
 
-        public override void VisitFromEndIndexOperation(IFromEndIndexOperation operation)
+        internal override void VisitFromEndIndexOperation(IFromEndIndexOperation operation)
         {
-            Assert.Equal(OperationKind.FromEndIndex, operation.Kind);
+            Assert.Equal(OperationKind.None, operation.Kind);
             Assert.Same(operation.Operand, operation.Children.Single());
         }