diff --git a/server/src/main/java/org/elasticsearch/TransportVersions.java b/server/src/main/java/org/elasticsearch/TransportVersions.java
index 6267fb3b86ae4..6b936284b18f7 100644
--- a/server/src/main/java/org/elasticsearch/TransportVersions.java
+++ b/server/src/main/java/org/elasticsearch/TransportVersions.java
@@ -134,6 +134,7 @@ static TransportVersion def(int id) {
     public static final TransportVersion NODE_INFO_REQUEST_SIMPLIFIED = def(8_510_00_0);
     public static final TransportVersion NESTED_KNN_VECTOR_QUERY_V = def(8_511_00_0);
     public static final TransportVersion ML_PACKAGE_LOADER_PLATFORM_ADDED = def(8_512_00_0);
+    public static final TransportVersion ELSER_SERVICE_MODEL_VERSION_ADDED_PATCH = def(8_512_00_1);
     public static final TransportVersion PLUGIN_DESCRIPTOR_OPTIONAL_CLASSNAME = def(8_513_00_0);
     public static final TransportVersion UNIVERSAL_PROFILING_LICENSE_ADDED = def(8_514_00_0);
     public static final TransportVersion ELSER_SERVICE_MODEL_VERSION_ADDED = def(8_515_00_0);
diff --git a/x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/services/elser/ElserMlNodeServiceSettings.java b/x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/services/elser/ElserMlNodeServiceSettings.java
index 7dffbc693ca51..d1f27302f85f1 100644
--- a/x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/services/elser/ElserMlNodeServiceSettings.java
+++ b/x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/services/elser/ElserMlNodeServiceSettings.java
@@ -87,10 +87,21 @@ public ElserMlNodeServiceSettings(int numAllocations, int numThreads, String var
     public ElserMlNodeServiceSettings(StreamInput in) throws IOException {
         numAllocations = in.readVInt();
         numThreads = in.readVInt();
-        if (in.getTransportVersion().onOrAfter(TransportVersions.ELSER_SERVICE_MODEL_VERSION_ADDED)) {
+        if (transportVersionIsCompatibleWithElserModelVersion(in.getTransportVersion())) {
             modelVariant = in.readString();
         } else {
-            modelVariant = ElserMlNodeService.ELSER_V1_MODEL;
+            modelVariant = ElserMlNodeService.ELSER_V2_MODEL;
+        }
+    }
+
+    static boolean transportVersionIsCompatibleWithElserModelVersion(TransportVersion transportVersion) {
+        var nextNonPatchVersion = TransportVersions.PLUGIN_DESCRIPTOR_OPTIONAL_CLASSNAME;
+
+        if (transportVersion.onOrAfter(TransportVersions.ELSER_SERVICE_MODEL_VERSION_ADDED)) {
+            return true;
+        } else {
+            return transportVersion.onOrAfter(TransportVersions.ELSER_SERVICE_MODEL_VERSION_ADDED_PATCH)
+                && transportVersion.before(nextNonPatchVersion);
         }
     }
 
@@ -130,7 +141,7 @@ public TransportVersion getMinimalSupportedVersion() {
     public void writeTo(StreamOutput out) throws IOException {
         out.writeVInt(numAllocations);
         out.writeVInt(numThreads);
-        if (out.getTransportVersion().onOrAfter(TransportVersions.ELSER_SERVICE_MODEL_VERSION_ADDED)) {
+        if (transportVersionIsCompatibleWithElserModelVersion(out.getTransportVersion())) {
             out.writeString(modelVariant);
         }
     }
diff --git a/x-pack/plugin/inference/src/test/java/org/elasticsearch/xpack/inference/services/elser/ElserMlNodeServiceSettingsTests.java b/x-pack/plugin/inference/src/test/java/org/elasticsearch/xpack/inference/services/elser/ElserMlNodeServiceSettingsTests.java
index 35d5c0b8e9603..8b6f3f1a56ba6 100644
--- a/x-pack/plugin/inference/src/test/java/org/elasticsearch/xpack/inference/services/elser/ElserMlNodeServiceSettingsTests.java
+++ b/x-pack/plugin/inference/src/test/java/org/elasticsearch/xpack/inference/services/elser/ElserMlNodeServiceSettingsTests.java
@@ -7,10 +7,12 @@
 
 package org.elasticsearch.xpack.inference.services.elser;
 
+import org.elasticsearch.TransportVersions;
 import org.elasticsearch.common.ValidationException;
 import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.test.AbstractWireSerializingTestCase;
 
+import java.io.IOException;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
@@ -85,6 +87,52 @@ public void testFromMapMissingOptions() {
         assertThat(e.getMessage(), containsString("[service_settings] does not contain the required setting [num_allocations]"));
     }
 
+    public void testTransportVersionIsCompatibleWithElserModelVersion() {
+        assertTrue(
+            ElserMlNodeServiceSettings.transportVersionIsCompatibleWithElserModelVersion(
+                TransportVersions.ELSER_SERVICE_MODEL_VERSION_ADDED
+            )
+        );
+        assertTrue(
+            ElserMlNodeServiceSettings.transportVersionIsCompatibleWithElserModelVersion(
+                TransportVersions.ELSER_SERVICE_MODEL_VERSION_ADDED_PATCH
+            )
+        );
+
+        assertFalse(
+            ElserMlNodeServiceSettings.transportVersionIsCompatibleWithElserModelVersion(TransportVersions.ML_PACKAGE_LOADER_PLATFORM_ADDED)
+        );
+        assertFalse(
+            ElserMlNodeServiceSettings.transportVersionIsCompatibleWithElserModelVersion(
+                TransportVersions.PLUGIN_DESCRIPTOR_OPTIONAL_CLASSNAME
+            )
+        );
+        assertFalse(
+            ElserMlNodeServiceSettings.transportVersionIsCompatibleWithElserModelVersion(
+                TransportVersions.UNIVERSAL_PROFILING_LICENSE_ADDED
+            )
+        );
+    }
+
+    public void testBwcWrite() throws IOException {
+        {
+            var settings = new ElserMlNodeServiceSettings(1, 1, ".elser_model_1");
+            var copy = copyInstance(settings, TransportVersions.ELSER_SERVICE_MODEL_VERSION_ADDED);
+            assertEquals(settings, copy);
+        }
+        {
+            var settings = new ElserMlNodeServiceSettings(1, 1, ".elser_model_1");
+            var copy = copyInstance(settings, TransportVersions.PLUGIN_DESCRIPTOR_OPTIONAL_CLASSNAME);
+            assertNotEquals(settings, copy);
+            assertEquals(".elser_model_2", copy.getModelVariant());
+        }
+        {
+            var settings = new ElserMlNodeServiceSettings(1, 1, ".elser_model_1");
+            var copy = copyInstance(settings, TransportVersions.ELSER_SERVICE_MODEL_VERSION_ADDED_PATCH);
+            assertEquals(settings, copy);
+        }
+    }
+
     public void testFromMapInvalidSettings() {
         var settingsMap = new HashMap<String, Object>(
             Map.of(ElserMlNodeServiceSettings.NUM_ALLOCATIONS, 0, ElserMlNodeServiceSettings.NUM_THREADS, -1)