Index: trunk/src/org/openstreetmap/josm/gui/dialogs/relation/actions/IRelationEditorActionAccess.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/dialogs/relation/actions/IRelationEditorActionAccess.java	(revision 18561)
+++ trunk/src/org/openstreetmap/josm/gui/dialogs/relation/actions/IRelationEditorActionAccess.java	(revision 18563)
@@ -6,4 +6,5 @@
 import org.openstreetmap.josm.data.osm.IRelation;
 import org.openstreetmap.josm.data.osm.Relation;
+import org.openstreetmap.josm.gui.MainApplication;
 import org.openstreetmap.josm.gui.dialogs.relation.IRelationEditor;
 import org.openstreetmap.josm.gui.dialogs.relation.MemberTable;
@@ -11,4 +12,5 @@
 import org.openstreetmap.josm.gui.dialogs.relation.SelectionTable;
 import org.openstreetmap.josm.gui.dialogs.relation.SelectionTableModel;
+import org.openstreetmap.josm.gui.layer.OsmDataLayer;
 import org.openstreetmap.josm.gui.tagging.TagEditorModel;
 import org.openstreetmap.josm.gui.tagging.ac.AutoCompletingTextField;
@@ -76,6 +78,11 @@
         final Relation newRelation;
         final Relation oldRelation = getEditor().getRelation();
-        if (oldRelation != null && oldRelation.getDataSet() != null && oldRelation.getDataSet().isLocked()) {
+        boolean isUploadInProgress = MainApplication.getLayerManager().getLayersOfType(OsmDataLayer.class)
+                .stream().anyMatch(OsmDataLayer::isUploadInProgress);
+        if (isUploadInProgress || oldRelation != null && oldRelation.getDataSet() != null && oldRelation.getDataSet().isLocked()) {
             // If the dataset is locked, then we cannot change the relation. See JOSM #22024.
+            // We should also avoid changing the relation if there is an upload in progress. See JOSM #22268/#22398.
+            // There appears to be a race condition where a dataset might not be locked in the check, then is locked while using the
+            // copy relation constructor.
             // This is due to the `setMembers` -> `addReferrer` call chain requires that the dataset is not read only.
             return oldRelation;