diff --git a/server/src/main/java/org/elasticsearch/repositories/blobstore/BlobStoreRepository.java b/server/src/main/java/org/elasticsearch/repositories/blobstore/BlobStoreRepository.java
index d354fdb7aac..6e09cd6ec30 100644
--- a/server/src/main/java/org/elasticsearch/repositories/blobstore/BlobStoreRepository.java
+++ b/server/src/main/java/org/elasticsearch/repositories/blobstore/BlobStoreRepository.java
@@ -404,6 +404,7 @@ public abstract class BlobStoreRepository extends AbstractLifecycleComponent imp
     public void updateState(ClusterState state) {
         metadata = getRepoMetadata(state);
         uncleanStart = uncleanStart && metadata.generation() != metadata.pendingGeneration();
+        final boolean wasBestEffortConsistency = bestEffortConsistency;
         bestEffortConsistency = uncleanStart || isReadOnly()
             || state.nodes().getMinNodeVersion().before(RepositoryMetadata.REPO_GEN_IN_CS_VERSION)
             || metadata.generation() == RepositoryData.UNKNOWN_REPO_GEN || ALLOW_CONCURRENT_MODIFICATION.get(metadata.settings());
@@ -430,8 +431,9 @@ public abstract class BlobStoreRepository extends AbstractLifecycleComponent imp
         } else {
             final long previousBest = latestKnownRepoGen.getAndSet(metadata.generation());
             if (previousBest != metadata.generation()) {
-                assert metadata.generation() == RepositoryData.CORRUPTED_REPO_GEN || previousBest < metadata.generation() :
-                    "Illegal move from repository generation [" + previousBest + "] to generation [" + metadata.generation() + "]";
+                assert wasBestEffortConsistency || metadata.generation() == RepositoryData.CORRUPTED_REPO_GEN
+                        || previousBest < metadata.generation() : "Illegal move from repository generation [" + previousBest
+                        + "] to generation [" + metadata.generation() + "]";
                 logger.debug("Updated repository generation from [{}] to [{}]", previousBest, metadata.generation());
             }
         }