diff --git a/src/FormMigration/Actions/TransferDonations.php b/src/FormMigration/Actions/TransferDonations.php
index d34b202466..f48b1e3777 100644
--- a/src/FormMigration/Actions/TransferDonations.php
+++ b/src/FormMigration/Actions/TransferDonations.php
@@ -13,12 +13,12 @@ public function __construct($sourceId)
         $this->sourceId = $sourceId;
     }
 
-    public static function from($sourceId): TransferDonations
+    public static function from($sourceId): self
     {
         return new TransferDonations($sourceId);
     }
 
-    public function to($destinationId)
+    public function to($destinationId): void
     {
         $this->__invoke($destinationId);
     }
diff --git a/src/FormMigration/Actions/TransferFormUrl.php b/src/FormMigration/Actions/TransferFormUrl.php
index 9c5243a3af..5c25fdadc5 100644
--- a/src/FormMigration/Actions/TransferFormUrl.php
+++ b/src/FormMigration/Actions/TransferFormUrl.php
@@ -11,12 +11,12 @@ public function __construct($sourceId)
         $this->sourceId = $sourceId;
     }
 
-    public static function from($sourceId): TransferFormUrl
+    public static function from($sourceId): self
     {
         return new TransferFormUrl($sourceId);
     }
 
-    public function to($destinationId)
+    public function to($destinationId): void
     {
         $this->__invoke($destinationId);
     }
diff --git a/src/FormMigration/DataTransferObjects/FormMigrationPayload.php b/src/FormMigration/DataTransferObjects/FormMigrationPayload.php
index 2e9f48c498..ab4546f478 100644
--- a/src/FormMigration/DataTransferObjects/FormMigrationPayload.php
+++ b/src/FormMigration/DataTransferObjects/FormMigrationPayload.php
@@ -19,8 +19,8 @@ public function __construct(DonationFormV2 $formV2, DonationFormV3 $formV3)
         $this->formV3 = $formV3;
     }
 
-    public static function fromFormV2(DonationFormV2 $formV2): FormMigrationPayload
+    public static function fromFormV2(DonationFormV2 $formV2): self
     {
-        return new FormMigrationPayload($formV2, DonationFormV3::factory()->create());
+        return new self($formV2, DonationFormV3::factory()->create());
     }
 }
diff --git a/src/FormMigration/DataTransferObjects/TransferOptions.php b/src/FormMigration/DataTransferObjects/TransferOptions.php
index 567a5e89fc..1717f3065a 100644
--- a/src/FormMigration/DataTransferObjects/TransferOptions.php
+++ b/src/FormMigration/DataTransferObjects/TransferOptions.php
@@ -22,18 +22,18 @@ public function __construct(bool $changeUrl, bool $delete, bool $redirect)
         $this->redirect = $redirect;
     }
 
-    public static function fromRequest(WP_REST_Request $request): TransferOptions
+    public static function fromRequest(WP_REST_Request $request): self
     {
-        return new TransferOptions(
+        return new self(
             $request->get_param('changeUrl'),
             $request->get_param('delete'),
             $request->get_param('redirect')
         );
     }
 
-    public static function fromArray($options): TransferOptions
+    public static function fromArray($options): self
     {
-        return new TransferOptions(
+        return new self(
             $options['changeUrl'],
             $options['delete'],
             $options['redirect']