diff --git a/rules/Symfony30/Rector/MethodCall/FormTypeInstanceToClassConstRector.php b/rules/Symfony30/Rector/MethodCall/FormTypeInstanceToClassConstRector.php
index 893e6992..ba3915a0 100644
--- a/rules/Symfony30/Rector/MethodCall/FormTypeInstanceToClassConstRector.php
+++ b/rules/Symfony30/Rector/MethodCall/FormTypeInstanceToClassConstRector.php
@@ -107,20 +107,29 @@ public function refactor(Node $node): ?Node
         }
 
         // special case for collections
+        $hasChangedCollection = false;
         if ($this->formCollectionAnalyzer->isCollectionType($node)) {
-            $this->refactorCollectionOptions($node);
+            $hasChangedCollection = $this->refactorCollectionOptions($node);
         }
 
-        return $this->formInstanceToFormClassConstFetchConverter->processNewInstance($node, 1, 2);
+        $newMethodCall = $this->formInstanceToFormClassConstFetchConverter->processNewInstance($node, 1, 2);
+        if ($newMethodCall instanceof MethodCall) {
+            return $newMethodCall;
+        }
+
+        // collection options were mutated in place, report the change via the return value
+        return $hasChangedCollection ? $node : null;
     }
 
-    private function refactorCollectionOptions(MethodCall $methodCall): void
+    private function refactorCollectionOptions(MethodCall $methodCall): bool
     {
         $optionsArray = $this->formOptionsArrayMatcher->match($methodCall);
         if (! $optionsArray instanceof Array_) {
-            return;
+            return false;
         }
 
+        $hasChanged = false;
+
         foreach ($optionsArray->items as $arrayItem) {
             if (! $arrayItem instanceof ArrayItem) {
                 continue;
@@ -145,6 +154,9 @@ private function refactorCollectionOptions(MethodCall $methodCall): void
             }
 
             $arrayItem->value = $this->nodeFactory->createClassConstReference($newClass->toString());
+            $hasChanged = true;
         }
+
+        return $hasChanged;
     }
 }