diff --git a/lib/Models/Newsletter.php b/lib/Models/Newsletter.php
index 076149c475..433fba7caf 100644
--- a/lib/Models/Newsletter.php
+++ b/lib/Models/Newsletter.php
@@ -24,7 +24,10 @@ use function MailPoetVendor\array_column;
  * @property string $type
  * @property object|array|bool $queue
  * @property string $hash
+ * @property string $senderName
  * @property string $senderAddress
+ * @property string $replyToName
+ * @property string $replyToAddress
  * @property string $status
  * @property string|object $meta
  * @property array $options
diff --git a/tasks/phpstan/phpstan-baseline-integration-tests.neon b/tasks/phpstan/phpstan-baseline-integration-tests.neon
index 94a58546d6..8c5d6ab4ad 100644
--- a/tasks/phpstan/phpstan-baseline-integration-tests.neon
+++ b/tasks/phpstan/phpstan-baseline-integration-tests.neon
@@ -52,12 +52,7 @@ parameters:
 
 		-
 			message: "#^Cannot call method asArray\\(\\) on MailPoet\\\\Models\\\\Newsletter\\|false\\.$#"
-			count: 6
-			path: ../../tests/integration/API/JSON/v1/NewslettersTest.php
-
-		-
-			message: "#^Cannot access property \\$subject on MailPoet\\\\Models\\\\Newsletter\\|false\\.$#"
-			count: 1
+			count: 5
 			path: ../../tests/integration/API/JSON/v1/NewslettersTest.php
 
 		-
diff --git a/tests/integration/API/JSON/v1/NewslettersTest.php b/tests/integration/API/JSON/v1/NewslettersTest.php
index c7fb9121a7..19ec360374 100644
--- a/tests/integration/API/JSON/v1/NewslettersTest.php
+++ b/tests/integration/API/JSON/v1/NewslettersTest.php
@@ -170,15 +170,31 @@ class NewslettersTest extends \MailPoetTest {
   public function testItCanSaveANewsletter() {
     $newsletterData = [
       'id' => $this->newsletter->id,
-      'subject' => 'My Updated Newsletter',
+      'type' => 'Updated type',
+      'subject' => 'Updated subject',
+      'preheader' => 'Updated preheader',
+      'body' => '{"value": "Updated body"}',
+      'sender_name' => 'Updated sender name',
+      'sender_address' => 'Updated sender address',
+      'reply_to_name' => 'Updated reply-to name',
+      'reply_to_address' => 'Updated reply-to address',
+      'ga_campaign' => 'Updated GA campaign',
     ];
 
     $response = $this->endpoint->save($newsletterData);
     expect($response->status)->equals(APIResponse::STATUS_OK);
     $updatedNewsletter = Newsletter::findOne($this->newsletter->id);
+    assert($updatedNewsletter instanceof Newsletter); // PHPStan
     expect($response->data)->equals($updatedNewsletter->asArray());
-    expect($updatedNewsletter->subject)->equals('My Updated Newsletter');
-
+    expect($updatedNewsletter->type)->equals('Updated type');
+    expect($updatedNewsletter->subject)->equals('Updated subject');
+    expect($updatedNewsletter->preheader)->equals('Updated preheader');
+    expect($updatedNewsletter->body)->equals('{"value":"Updated body"}');
+    expect($updatedNewsletter->senderName)->equals('Updated sender name');
+    expect($updatedNewsletter->senderAddress)->equals('Updated sender address');
+    expect($updatedNewsletter->replyToName)->equals('Updated reply-to name');
+    expect($updatedNewsletter->replyToAddress)->equals('Updated reply-to address');
+    expect($updatedNewsletter->gaCampaign)->equals('Updated GA campaign');
   }
 
   public function testItReturnsErrorIfSubscribersLimitReached() {
diff --git a/tests/integration/Newsletter/NewsletterSaveControllerTest.php b/tests/integration/Newsletter/NewsletterSaveControllerTest.php
index d49c2b8930..2dcabfa8d0 100644
--- a/tests/integration/Newsletter/NewsletterSaveControllerTest.php
+++ b/tests/integration/Newsletter/NewsletterSaveControllerTest.php
@@ -31,11 +31,27 @@ class NewsletterSaveControllerTest extends \MailPoetTest {
     $newsletter = $this->createNewsletter(NewsletterEntity::TYPE_STANDARD);
     $newsletterData = [
       'id' => $newsletter->getId(),
+      'type' => 'Updated type',
       'subject' => 'Updated subject',
+      'preheader' => 'Updated preheader',
+      'body' => '{"value": "Updated body"}',
+      'sender_name' => 'Updated sender name',
+      'sender_address' => 'Updated sender address',
+      'reply_to_name' => 'Updated reply-to name',
+      'reply_to_address' => 'Updated reply-to address',
+      'ga_campaign' => 'Updated GA campaign',
     ];
 
     $newsletter = $this->saveController->save($newsletterData);
+    expect($newsletter->getType())->equals('Updated type');
     expect($newsletter->getSubject())->equals('Updated subject');
+    expect($newsletter->getPreheader())->equals('Updated preheader');
+    expect($newsletter->getBody())->equals(['value' => 'Updated body']);
+    expect($newsletter->getSenderName())->equals('Updated sender name');
+    expect($newsletter->getSenderAddress())->equals('Updated sender address');
+    expect($newsletter->getReplyToName())->equals('Updated reply-to name');
+    expect($newsletter->getReplyToAddress())->equals('Updated reply-to address');
+    expect($newsletter->getGaCampaign())->equals('Updated GA campaign');
   }
 
   public function testItDoesNotRerenderPostNotificationsUponUpdate() {