diff --git a/frontend/src/Settings/Applications/Listenarr/Listenarr.tsx b/frontend/src/Settings/Applications/Listenarr/Listenarr.tsx
deleted file mode 100644
index 62d3075c3..000000000
--- a/frontend/src/Settings/Applications/Listenarr/Listenarr.tsx
+++ /dev/null
@@ -1,20 +0,0 @@
-import React from 'react';
-import EditApplicationModalConnector from 'Settings/Applications/Applications/EditApplicationModalConnector';
-import Application from 'typings/Application';
-
-interface ListenarrProps {
-  selectedApplication: Application;
-  onModalClose: () => void;
-}
-
-function Listenarr({ selectedApplication, onModalClose }: ListenarrProps) {
-  return (
-    <EditApplicationModalConnector
-      isOpen={true}
-      item={selectedApplication}
-      onModalClose={onModalClose}
-    />
-  );
-}
-
-export default Listenarr;
diff --git a/src/NzbDrone.Core.Test/Applications/Listenarr/ListenarrFixture.cs b/src/NzbDrone.Core.Test/Applications/Listenarr/ListenarrFixture.cs
index dade03d40..5f5f0fccd 100644
--- a/src/NzbDrone.Core.Test/Applications/Listenarr/ListenarrFixture.cs
+++ b/src/NzbDrone.Core.Test/Applications/Listenarr/ListenarrFixture.cs
@@ -27,9 +27,9 @@ public void Setup()
                 Settings = new ListenarrSettings
                 {
                     ProwlarrUrl = "http://localhost:9696",
-                    BaseUrl = "http://localhost:5000",
+                    BaseUrl = "http://localhost:4545",
                     ApiKey = "abc",
-                    SyncCategories = new List<int> { NewznabStandardCategory.Movies.Id }
+                    SyncCategories = new List<int> { NewznabStandardCategory.AudioAudiobook.Id }
                 }
             };
 
@@ -223,18 +223,14 @@ public void Test_should_fail_when_schema_missing()
             // Arrange
             Mocker.GetMock<IListenarrV1Proxy>().Setup(c => c.GetIndexerSchema(It.IsAny<ListenarrSettings>())).Returns(new List<ListenarrIndexer>());
 
-            // Act & Assert
-            try
-            {
-                var result = Subject.Test();
-                result.IsValid.Should().BeFalse();
-                result.Errors.Should().ContainSingle(e => e.ErrorMessage.Contains("indexer schema"));
-            }
-            finally
-            {
-                // Consume expected warnings even if Subject.Test throws or an assert fails so teardown does not fail
-                ExceptionVerification.IgnoreWarns();
-            }
+            // Act & Assert - call private BuildListenarrIndexer to assert it throws
+            var method = typeof(NzbDrone.Core.Applications.Listenarr.Listenarr).GetMethod("BuildListenarrIndexer", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
+            var indexerDef = new IndexerDefinition { Id = 1, Name = "Test", Protocol = DownloadProtocol.Usenet, Capabilities = new IndexerCapabilities() };
+
+            var ex = Assert.Throws<System.Reflection.TargetInvocationException>(() => method.Invoke(Subject, new object[] { indexerDef, indexerDef.Capabilities, DownloadProtocol.Usenet, 0 }));
+            Assert.IsInstanceOf<ApplicationException>(ex.InnerException);
+            Assert.That(ex.InnerException.Message, Does.Contain("indexer schemas"));
+            ExceptionVerification.ExpectedWarns(1);
         }
 
         [Test]
@@ -290,7 +286,7 @@ public void AddIndexer_should_insert_app_indexer_mapping_on_success()
             };
 
             // Add a category that matches Settings.SyncCategories
-            indexerDefinition.Capabilities.Categories.AddCategoryMapping(1, NewznabStandardCategory.Movies);
+            indexerDefinition.Capabilities.Categories.AddCategoryMapping(1, NewznabStandardCategory.AudioAudiobook);
 
             var mockIndexer = new Mock<IIndexer>();
             mockIndexer.Setup(i => i.GetCapabilities()).Returns(indexerDefinition.Capabilities);
@@ -331,5 +327,75 @@ public void AddIndexer_should_insert_app_indexer_mapping_on_success()
             Mocker.GetMock<IListenarrV1Proxy>().Verify(m => m.AddIndexer(It.IsAny<ListenarrIndexer>(), It.IsAny<ListenarrSettings>()), Times.Once());
             Mocker.GetMock<IAppIndexerMapService>().Verify(m => m.Insert(It.Is<AppIndexerMap>(a => a.IndexerId == 12 && a.RemoteIndexerId == 501)), Times.Once());
         }
+
+        [Test]
+        public void AddIndexer_should_use_existing_remote_indexer_if_baseUrl_matches()
+        {
+            // Arrange
+            var indexerDefinition = new IndexerDefinition
+            {
+                Id = 12,
+                Name = "TestIndexer",
+                Protocol = DownloadProtocol.Usenet,
+                Capabilities = new IndexerCapabilities(),
+                Enable = true,
+                AppProfile = new LazyLoaded<AppSyncProfile>(new AppSyncProfile { EnableRss = true, EnableAutomaticSearch = true, EnableInteractiveSearch = true })
+            };
+
+            indexerDefinition.Capabilities.Categories.AddCategoryMapping(1, NewznabStandardCategory.AudioAudiobook);
+
+            var mockIndexer = new Mock<IIndexer>();
+            mockIndexer.Setup(i => i.GetCapabilities()).Returns(indexerDefinition.Capabilities);
+
+            Mocker.GetMock<IIndexerFactory>().Setup(m => m.GetInstance(It.IsAny<IndexerDefinition>())).Returns(mockIndexer.Object);
+
+            var schema = new List<ListenarrIndexer>
+            {
+                new ListenarrIndexer
+                {
+                    Implementation = "Newznab",
+                    Fields = new List<ListenarrField>
+                    {
+                        new ListenarrField { Name = "baseUrl", Value = "" },
+                        new ListenarrField { Name = "apiPath", Value = "" },
+                        new ListenarrField { Name = "apiKey", Value = "" },
+                        new ListenarrField { Name = "categories", Value = new List<int>() }
+                    }
+                }
+            };
+
+            // Existing remote indexer with matching baseUrl
+            var existing = new ListenarrIndexer
+            {
+                Id = 501,
+                Implementation = "Newznab",
+                Fields = new List<ListenarrField>
+                {
+                    new ListenarrField { Name = "baseUrl", Value = $"{((ListenarrSettings)Subject.Definition.Settings).ProwlarrUrl.TrimEnd('/')}/12/" },
+                    new ListenarrField { Name = "apiPath", Value = "/api" },
+                    new ListenarrField { Name = "apiKey", Value = "abc" },
+                    new ListenarrField { Name = "categories", Value = new List<int>() }
+                }
+            };
+
+            Mocker.GetMock<IListenarrV1Proxy>().Setup(c => c.GetIndexerSchema(It.IsAny<ListenarrSettings>())).Returns(schema);
+            Mocker.GetMock<IListenarrV1Proxy>().Setup(c => c.GetIndexers(It.IsAny<ListenarrSettings>())).Returns(new List<ListenarrIndexer> { existing });
+
+            // Ensure the private schema cache will execute the factory so it invokes our mocked proxy
+            var cachedForTest = new Mock<ICached<System.Collections.Generic.List<ListenarrIndexer>>>();
+            cachedForTest.Setup(c => c.Get(It.IsAny<string>(), It.IsAny<Func<System.Collections.Generic.List<ListenarrIndexer>>>(), It.IsAny<TimeSpan>()))
+                         .Returns<string, Func<System.Collections.Generic.List<ListenarrIndexer>>, TimeSpan>((k, f, t) => f());
+            typeof(NzbDrone.Core.Applications.Listenarr.Listenarr).GetField("_schemaCache", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic).SetValue(Subject, cachedForTest.Object);
+
+            // pre-check
+            indexerDefinition.Capabilities.Categories.SupportedCategories(((ListenarrSettings)Subject.Definition.Settings).SyncCategories.ToArray()).Should().NotBeEmpty();
+
+            // Act
+            Subject.AddIndexer(indexerDefinition);
+
+            // Assert - AddIndexer should not be called because remote already exists
+            Mocker.GetMock<IListenarrV1Proxy>().Verify(m => m.AddIndexer(It.IsAny<ListenarrIndexer>(), It.IsAny<ListenarrSettings>()), Times.Never());
+            Mocker.GetMock<IAppIndexerMapService>().Verify(m => m.Insert(It.Is<AppIndexerMap>(a => a.IndexerId == 12 && a.RemoteIndexerId == 501)), Times.Once());
+        }
     }
 }
diff --git a/src/NzbDrone.Core/Applications/Listenarr/Listenarr.cs b/src/NzbDrone.Core/Applications/Listenarr/Listenarr.cs
index 485e31175..a10417e61 100644
--- a/src/NzbDrone.Core/Applications/Listenarr/Listenarr.cs
+++ b/src/NzbDrone.Core/Applications/Listenarr/Listenarr.cs
@@ -391,7 +391,7 @@ private ListenarrIndexer BuildListenarrIndexer(IndexerDefinition indexer, Indexe
             if (id == 0)
             {
                 // Ensuring backward compatibility with older versions on first sync
-                syncFields.AddRange(new List<string> { "earlyReleaseLimit", "additionalParameters" });
+                syncFields.AddRange(new List<string> { "additionalParameters" });
             }
 
             var newznab = schemas.FirstOrDefault(i => i.Implementation == "Newznab");
diff --git a/src/NzbDrone.Core/Applications/Listenarr/ListenarrV1Proxy.cs b/src/NzbDrone.Core/Applications/Listenarr/ListenarrV1Proxy.cs
index c5499cb43..ca7f9da76 100644
--- a/src/NzbDrone.Core/Applications/Listenarr/ListenarrV1Proxy.cs
+++ b/src/NzbDrone.Core/Applications/Listenarr/ListenarrV1Proxy.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using System.Net;
 using System.Net.Http;
 using FluentValidation.Results;
@@ -64,26 +65,12 @@ public ListenarrIndexer GetIndexer(int indexerId, ListenarrSettings settings)
         {
             try
             {
-                var request = BuildRequest(settings, $"{AppIndexerApiRoute}/{indexerId}", HttpMethod.Get);
-                return Execute<ListenarrIndexer>(request);
+                var fallback = BuildRequest(settings, $"{AppApiRoute}/indexers/{indexerId}", HttpMethod.Get);
+                return Execute<ListenarrIndexer>(fallback);
             }
-            catch (HttpException ex)
+            catch (HttpException)
             {
-                if (ex.Response.StatusCode != HttpStatusCode.NotFound)
-                {
-                    throw;
-                }
-
-                // Try plural form as a fallback
-                try
-                {
-                    var fallback = BuildRequest(settings, $"{AppApiRoute}/indexers/{indexerId}", HttpMethod.Get);
-                    return Execute<ListenarrIndexer>(fallback);
-                }
-                catch (HttpException)
-                {
-                    return null;
-                }
+                return null;
             }
         }
 
@@ -293,6 +280,35 @@ public List<ListenarrIndexer> GetIndexerSchema(ListenarrSettings settings)
 
         public ListenarrIndexer AddIndexer(ListenarrIndexer indexer, ListenarrSettings settings)
         {
+            // Defensive check: avoid creating duplicates if an indexer with the same baseUrl already exists on the remote app.
+            try
+            {
+                var incomingBaseUrl = indexer?.Fields?.FirstOrDefault(f => f.Name == "baseUrl")?.Value as string;
+                if (!string.IsNullOrWhiteSpace(incomingBaseUrl))
+                {
+                    var existing = GetIndexers(settings);
+                    if (existing != null)
+                    {
+                        var match = existing.FirstOrDefault(e =>
+                            string.Equals(
+                                (e.Fields?.FirstOrDefault(f => f.Name == "baseUrl")?.Value as string)?.TrimEnd('/'),
+                                incomingBaseUrl.TrimEnd('/'),
+                                StringComparison.InvariantCultureIgnoreCase));
+
+                        if (match != null)
+                        {
+                            _logger.Debug("Found existing remote indexer matching baseUrl; skipping add and returning existing id {0}", match.Id);
+                            return match;
+                        }
+                    }
+                }
+            }
+            catch (Exception ex)
+            {
+                // If the existence check fails for any reason, proceed with the add flow and let any resulting errors bubble up.
+                _logger.Debug(ex, "Failed to run pre-flight existence check before AddIndexer; proceeding to create");
+            }
+
             var request = BuildRequest(settings, $"{AppIndexerApiRoute}", HttpMethod.Post);
 
             request.SetContent(indexer.ToJson());