diff --git a/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/common/DataPageToolkit.java b/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/common/DataPageToolkit.java
index 529d73a2b..68f0135ee 100644
--- a/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/common/DataPageToolkit.java
+++ b/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/common/DataPageToolkit.java
@@ -641,13 +641,12 @@ public static IXDataRenderer buildSpanRenderer(IItemCollection pathItems, IColor
 
 	public static boolean addEndTimeLines(
 		XYDataRenderer renderer, IItemCollection items, boolean fill, Stream<IAttribute<IQuantity>> yAttributes) {
-		// FIXME: JMC-4520 - Handle multiple item iterables
-		Iterator<IItemIterable> ii = items.iterator();
-		if (ii.hasNext()) {
-			IItemIterable itemStream = ii.next();
-			IType<IItem> type = itemStream.getType();
-			// FIXME: A better way to ensure sorting by endTime
-			return yAttributes.peek(a -> addEndTimeLine(renderer, itemStream.iterator(), type, a, fill))
+		if (items.hasItems()) {
+			Iterator<IItemIterable> ii = items.iterator();
+			IType<IItem> type = ii.hasNext() ? ii.next().getType() : null;
+			List<IItem> allItems = new ArrayList<>();
+			items.forEach(itemStream -> itemStream.forEach(allItems::add));
+			return yAttributes.peek(a -> addEndTimeLine(renderer, allItems.iterator(), type, a, fill))
 					.mapToLong(a -> 1L).sum() > 0;
 		}
 		return false;
diff --git a/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/pages/itemhandler/AttributeComponentConfiguration.java b/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/pages/itemhandler/AttributeComponentConfiguration.java
index 57a52e968..893b0e080 100644
--- a/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/pages/itemhandler/AttributeComponentConfiguration.java
+++ b/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/pages/itemhandler/AttributeComponentConfiguration.java
@@ -33,7 +33,6 @@
 package org.openjdk.jmc.flightrecorder.ui.pages.itemhandler;
 
 import java.util.HashMap;
-import java.util.Iterator;
 import java.util.Map;
 import java.util.Map.Entry;
 
@@ -73,7 +72,7 @@ public AttributeComponentConfiguration(IItemCollection items) {
 		uncommonChartableAttributes = new HashMap<>();
 		lineChartableAttributes = new HashMap<>();
 		forEachType(items);
-		populateAttributeMaps(isSuitableForLineCharts(items, allTypes));
+		populateAttributeMaps(isSuitableForLineCharts(allTypes));
 	}
 
 	@SuppressWarnings("deprecation")
@@ -117,16 +116,8 @@ private void populateAttributeMaps(boolean allowLineCharts) {
 		}
 	}
 
-	private static boolean isSuitableForLineCharts(IItemCollection items, Map<String, IType<?>> types) {
-		// NOTE: JMC-4520 - Only allowing line charts for one event type, which only has one event array. 
-		if (types.values().size() == 1) {
-			Iterator<IItemIterable> iterator = items.iterator();
-			if (iterator.hasNext()) {
-				iterator.next();
-				return !iterator.hasNext();
-			}
-		}
-		return false;
+	private static boolean isSuitableForLineCharts(Map<String, IType<?>> types) {
+		return types.values().size() == 1;
 	}
 
 	public Map<String, IAttribute<?>> getAllAttributes() {
diff --git a/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/pages/itemhandler/ItemChart.java b/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/pages/itemhandler/ItemChart.java
index 31c45d776..fb1d269cb 100644
--- a/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/pages/itemhandler/ItemChart.java
+++ b/application/org.openjdk.jmc.flightrecorder.ui/src/main/java/org/openjdk/jmc/flightrecorder/ui/pages/itemhandler/ItemChart.java
@@ -62,6 +62,7 @@
 import org.openjdk.jmc.common.item.Aggregators;
 import org.openjdk.jmc.common.item.IAggregator;
 import org.openjdk.jmc.common.item.IAttribute;
+import org.openjdk.jmc.common.item.IItem;
 import org.openjdk.jmc.common.item.IItemCollection;
 import org.openjdk.jmc.common.item.IItemIterable;
 import org.openjdk.jmc.common.item.IType;
@@ -540,19 +541,18 @@ private Collection<ItemRow> updateLineChart(IItemCollection itemsToChart) {
 							description);
 					for (IAttribute<?> attribute : attributes) {
 						// TODO: something other than time on x-axis?
-						Iterator<IItemIterable> chartItemsWithAttributeSomeType = itemsToChart
-								.apply(ItemFilters.hasAttribute(attribute)).iterator();
-						if (chartItemsWithAttributeSomeType.hasNext()
-								&& attribute.getContentType() instanceof LinearKindOfQuantity) {
-							IItemIterable is = chartItemsWithAttributeSomeType.next();
-							if (chartItemsWithAttributeSomeType.hasNext()) {
-								// FIXME: JMC-4520 - Add support for multiple item iterables
-								FlightRecorderUI.getDefault().getLogger().log(Level.INFO,
-										"Only charting a subset of the events!"); //$NON-NLS-1$
+						if (attribute.getContentType() instanceof LinearKindOfQuantity) {
+							IItemCollection itemsWithAttributeSomeType = itemsToChart
+									.apply(ItemFilters.hasAttribute(attribute));
+							if (itemsWithAttributeSomeType.hasItems()) {
+								Iterator<IItemIterable> iterator = itemsWithAttributeSomeType.iterator();
+								IType<IItem> type = iterator.hasNext() ? iterator.next().getType() : null;
+								List<IItem> allItems = new ArrayList<>();
+								itemsWithAttributeSomeType.forEach(itemStream -> itemStream.forEach(allItems::add));
+								@SuppressWarnings("unchecked")
+								IAttribute<IQuantity> qAttribute = (IAttribute<IQuantity>) attribute;
+								DataPageToolkit.addEndTimeLine(xyRenderer, allItems.iterator(), type, qAttribute, fill);
 							}
-							@SuppressWarnings("unchecked")
-							IAttribute<IQuantity> qAttribute = (IAttribute<IQuantity>) attribute;
-							DataPageToolkit.addEndTimeLine(xyRenderer, is.iterator(), is.getType(), qAttribute, fill);
 						}
 					}
 					rows.add(new ItemRow(name, description, xyRenderer, itemsToChart));