diff --git a/x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/MlConfigMigrator.java b/x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/MlConfigMigrator.java
index f2fe80f3776..184ee44cf37 100644
--- a/x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/MlConfigMigrator.java
+++ b/x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/MlConfigMigrator.java
@@ -37,6 +37,7 @@ import org.elasticsearch.persistent.PersistentTasksCustomMetaData;
 import org.elasticsearch.xpack.core.ml.MlMetadata;
 import org.elasticsearch.xpack.core.ml.MlTasks;
 import org.elasticsearch.xpack.core.ml.datafeed.DatafeedConfig;
+import org.elasticsearch.xpack.core.ml.job.config.AnalysisLimits;
 import org.elasticsearch.xpack.core.ml.job.config.Job;
 import org.elasticsearch.xpack.core.ml.job.persistence.AnomalyDetectorsIndex;
 import org.elasticsearch.xpack.core.ml.job.persistence.ElasticsearchMappings;
@@ -403,11 +404,23 @@ public class MlConfigMigrator {
         Map<String, Object> custom = job.getCustomSettings() == null ? new HashMap<>() : new HashMap<>(job.getCustomSettings());
         custom.put(MIGRATED_FROM_VERSION, job.getJobVersion());
         builder.setCustomSettings(custom);
+        // Increase the model memory limit for 6.1 - 6.3 jobs
+        Version jobVersion = job.getJobVersion();
+        if (jobVersion != null && jobVersion.onOrAfter(Version.V_6_1_0) && jobVersion.before(Version.V_6_3_0)) {
+            // Increase model memory limit if < 512MB
+            if (job.getAnalysisLimits() != null && job.getAnalysisLimits().getModelMemoryLimit() != null &&
+                    job.getAnalysisLimits().getModelMemoryLimit() < 512L) {
+                long updatedModelMemoryLimit = (long) (job.getAnalysisLimits().getModelMemoryLimit() * 1.3);
+                AnalysisLimits limits = new AnalysisLimits(updatedModelMemoryLimit,
+                        job.getAnalysisLimits().getCategorizationExamplesLimit());
+                builder.setAnalysisLimits(limits);
+            }
+        }
         // Pre v5.5 (ml beta) jobs do not have a version.
         // These jobs cannot be opened, we rely on the missing version
         // to indicate this.
         // See TransportOpenJobAction.validate()
-        if (job.getJobVersion() != null) {
+        if (jobVersion != null) {
             builder.setJobVersion(Version.CURRENT);
         }
         return builder.build();
diff --git a/x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/action/TransportOpenJobAction.java b/x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/action/TransportOpenJobAction.java
index 21f97cbb5dc..fad24247834 100644
--- a/x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/action/TransportOpenJobAction.java
+++ b/x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/action/TransportOpenJobAction.java
@@ -55,9 +55,6 @@ import org.elasticsearch.xpack.core.ml.MlMetaIndex;
 import org.elasticsearch.xpack.core.ml.MlTasks;
 import org.elasticsearch.xpack.core.ml.action.FinalizeJobExecutionAction;
 import org.elasticsearch.xpack.core.ml.action.OpenJobAction;
-import org.elasticsearch.xpack.core.ml.action.PutJobAction;
-import org.elasticsearch.xpack.core.ml.action.UpdateJobAction;
-import org.elasticsearch.xpack.core.ml.job.config.AnalysisLimits;
 import org.elasticsearch.xpack.core.ml.job.config.DetectionRule;
 import org.elasticsearch.xpack.core.ml.job.config.Job;
 import org.elasticsearch.xpack.core.ml.job.config.JobState;
@@ -540,50 +537,16 @@ public class TransportOpenJobAction extends TransportMasterNodeAction<OpenJobAct
             );
 
             // Tell the job tracker to refresh the memory requirement for this job and all other jobs that have persistent tasks
-            ActionListener<PutJobAction.Response> jobUpdateListener = ActionListener.wrap(
+            ActionListener<Boolean> jobUpdateListener = ActionListener.wrap(
                 response -> memoryTracker.refreshJobMemoryAndAllOthers(jobParams.getJobId(), memoryRequirementRefreshListener),
                 listener::onFailure
             );
 
-            // Increase the model memory limit for 6.1 - 6.3 jobs
-            ActionListener<Boolean> missingMappingsListener = ActionListener.wrap(
-                    response -> {
-                        Job job = jobParams.getJob();
-                        if (job != null) {
-                            Version jobVersion = job.getJobVersion();
-                            if (jobVersion != null &&
-                                    (jobVersion.onOrAfter(Version.V_6_1_0) && jobVersion.before(Version.V_6_3_0))) {
-                                // Increase model memory limit if < 512MB
-                                if (job.getAnalysisLimits() != null && job.getAnalysisLimits().getModelMemoryLimit() != null &&
-                                        job.getAnalysisLimits().getModelMemoryLimit() < 512L) {
-
-                                    long updatedModelMemoryLimit = (long) (job.getAnalysisLimits().getModelMemoryLimit() * 1.3);
-                                    AnalysisLimits limits = new AnalysisLimits(updatedModelMemoryLimit,
-                                            job.getAnalysisLimits().getCategorizationExamplesLimit());
-
-                                    JobUpdate update = new JobUpdate.Builder(job.getId()).setJobVersion(Version.CURRENT)
-                                            .setAnalysisLimits(limits).build();
-                                    UpdateJobAction.Request updateRequest = UpdateJobAction.Request.internal(job.getId(), update);
-                                    executeAsyncWithOrigin(client, ML_ORIGIN, UpdateJobAction.INSTANCE, updateRequest,
-                                            jobUpdateListener);
-                                } else {
-                                    jobUpdateListener.onResponse(null);
-                                }
-                            }
-                            else {
-                                jobUpdateListener.onResponse(null);
-                            }
-                        } else {
-                            jobUpdateListener.onResponse(null);
-                        }
-                    }, listener::onFailure
-            );
-
             // Try adding state doc mapping
             ActionListener<Boolean> resultsPutMappingHandler = ActionListener.wrap(
                     response -> {
                         addDocMappingIfMissing(AnomalyDetectorsIndex.jobStateIndexName(), ElasticsearchMappings::stateMapping,
-                                state, missingMappingsListener);
+                                state, jobUpdateListener);
                     }, listener::onFailure
             );