diff --git a/server/src/main/java/org/elasticsearch/index/IndexVersions.java b/server/src/main/java/org/elasticsearch/index/IndexVersions.java
index 1dd12dbe0322a..3bc3c82288122 100644
--- a/server/src/main/java/org/elasticsearch/index/IndexVersions.java
+++ b/server/src/main/java/org/elasticsearch/index/IndexVersions.java
@@ -139,6 +139,7 @@ private static Version parseUnchecked(String version) {
     public static final IndexVersion SYNTHETIC_SOURCE_STORE_ARRAYS_NATIVELY_BACKPORT_8_X = def(8_527_0_00, Version.LUCENE_9_12_1);
     public static final IndexVersion ADD_RESCORE_PARAMS_TO_QUANTIZED_VECTORS_BACKPORT_8_X = def(8_528_0_00, Version.LUCENE_9_12_1);
     public static final IndexVersion RESCORE_PARAMS_ALLOW_ZERO_TO_QUANTIZED_VECTORS_BACKPORT_8_X = def(8_529_0_00, Version.LUCENE_9_12_1);
+    public static final IndexVersion DEFAULT_OVERSAMPLE_VALUE_FOR_BBQ_BACKPORT_8_X = def(8_530_0_00, Version.LUCENE_9_12_1);
     public static final IndexVersion UPGRADE_TO_LUCENE_10_0_0 = def(9_000_0_00, Version.LUCENE_10_0_0);
     public static final IndexVersion LOGSDB_DEFAULT_IGNORE_DYNAMIC_BEYOND_LIMIT = def(9_001_0_00, Version.LUCENE_10_0_0);
     public static final IndexVersion TIME_BASED_K_ORDERED_DOC_ID = def(9_002_0_00, Version.LUCENE_10_0_0);
diff --git a/server/src/main/java/org/elasticsearch/index/mapper/vectors/DenseVectorFieldMapper.java b/server/src/main/java/org/elasticsearch/index/mapper/vectors/DenseVectorFieldMapper.java
index 7198338daf7e2..ea889d69b7304 100644
--- a/server/src/main/java/org/elasticsearch/index/mapper/vectors/DenseVectorFieldMapper.java
+++ b/server/src/main/java/org/elasticsearch/index/mapper/vectors/DenseVectorFieldMapper.java
@@ -95,8 +95,6 @@
 
 import static org.elasticsearch.common.Strings.format;
 import static org.elasticsearch.common.xcontent.XContentParserUtils.ensureExpectedToken;
-import static org.elasticsearch.index.IndexVersions.DEFAULT_DENSE_VECTOR_TO_INT8_HNSW;
-import static org.elasticsearch.index.IndexVersions.RESCORE_PARAMS_ALLOW_ZERO_TO_QUANTIZED_VECTORS;
 
 /**
  * A {@link FieldMapper} for indexing a dense vector of floats.
@@ -116,19 +114,23 @@ private static boolean hasRescoreIndexVersion(IndexVersion version) {
     }
 
     private static boolean allowsZeroRescore(IndexVersion version) {
-        return version.onOrAfter(RESCORE_PARAMS_ALLOW_ZERO_TO_QUANTIZED_VECTORS)
+        return version.onOrAfter(IndexVersions.RESCORE_PARAMS_ALLOW_ZERO_TO_QUANTIZED_VECTORS)
             || version.between(
                 IndexVersions.RESCORE_PARAMS_ALLOW_ZERO_TO_QUANTIZED_VECTORS_BACKPORT_8_X,
                 IndexVersions.UPGRADE_TO_LUCENE_10_0_0
             );
     }
 
+    private static boolean defaultOversampleForBBQ(IndexVersion version) {
+        return version.onOrAfter(IndexVersions.DEFAULT_OVERSAMPLE_VALUE_FOR_BBQ)
+            || version.between(IndexVersions.DEFAULT_OVERSAMPLE_VALUE_FOR_BBQ_BACKPORT_8_X, IndexVersions.UPGRADE_TO_LUCENE_10_0_0);
+    }
+
     public static final IndexVersion MAGNITUDE_STORED_INDEX_VERSION = IndexVersions.V_7_5_0;
     public static final IndexVersion INDEXED_BY_DEFAULT_INDEX_VERSION = IndexVersions.FIRST_DETACHED_INDEX_VERSION;
     public static final IndexVersion NORMALIZE_COSINE = IndexVersions.NORMALIZED_VECTOR_COSINE;
-    public static final IndexVersion DEFAULT_TO_INT8 = DEFAULT_DENSE_VECTOR_TO_INT8_HNSW;
+    public static final IndexVersion DEFAULT_TO_INT8 = IndexVersions.DEFAULT_DENSE_VECTOR_TO_INT8_HNSW;
     public static final IndexVersion LITTLE_ENDIAN_FLOAT_STORED_INDEX_VERSION = IndexVersions.V_8_9_0;
-    public static final IndexVersion DEFAULT_OVERSAMPLE_VALUE_FOR_BBQ = IndexVersions.DEFAULT_OVERSAMPLE_VALUE_FOR_BBQ;
 
     public static final NodeFeature RESCORE_VECTOR_QUANTIZED_VECTOR_MAPPING = new NodeFeature("mapper.dense_vector.rescore_vector");
     public static final NodeFeature RESCORE_ZERO_VECTOR_QUANTIZED_VECTOR_MAPPING = new NodeFeature(
@@ -202,7 +204,7 @@ public Builder(String name, IndexVersion indexVersionCreated) {
             super(name);
             this.indexVersionCreated = indexVersionCreated;
             final boolean indexedByDefault = indexVersionCreated.onOrAfter(INDEXED_BY_DEFAULT_INDEX_VERSION);
-            final boolean defaultInt8Hnsw = indexVersionCreated.onOrAfter(DEFAULT_DENSE_VECTOR_TO_INT8_HNSW);
+            final boolean defaultInt8Hnsw = indexVersionCreated.onOrAfter(IndexVersions.DEFAULT_DENSE_VECTOR_TO_INT8_HNSW);
             this.indexed = Parameter.indexParam(m -> toType(m).fieldType().indexed, indexedByDefault);
             if (indexedByDefault) {
                 // Only serialize on newer index versions to prevent breaking existing indices when upgrading
@@ -1498,7 +1500,7 @@ public IndexOptions parseIndexOptions(String fieldName, Map<String, ?> indexOpti
                 RescoreVector rescoreVector = null;
                 if (hasRescoreIndexVersion(indexVersion)) {
                     rescoreVector = RescoreVector.fromIndexOptions(indexOptionsMap, indexVersion);
-                    if (rescoreVector == null && indexVersion.onOrAfter(DEFAULT_OVERSAMPLE_VALUE_FOR_BBQ)) {
+                    if (rescoreVector == null && defaultOversampleForBBQ(indexVersion)) {
                         rescoreVector = new RescoreVector(DEFAULT_OVERSAMPLE);
                     }
                 }
@@ -1522,7 +1524,7 @@ public IndexOptions parseIndexOptions(String fieldName, Map<String, ?> indexOpti
                 RescoreVector rescoreVector = null;
                 if (hasRescoreIndexVersion(indexVersion)) {
                     rescoreVector = RescoreVector.fromIndexOptions(indexOptionsMap, indexVersion);
-                    if (rescoreVector == null && indexVersion.onOrAfter(DEFAULT_OVERSAMPLE_VALUE_FOR_BBQ)) {
+                    if (rescoreVector == null && defaultOversampleForBBQ(indexVersion)) {
                         rescoreVector = new RescoreVector(DEFAULT_OVERSAMPLE);
                     }
                 }