diff --git a/CRM/Mailing/BAO/Mailing.php b/CRM/Mailing/BAO/Mailing.php
index 83a73baa681e..f6b624f4aadc 100644
--- a/CRM/Mailing/BAO/Mailing.php
+++ b/CRM/Mailing/BAO/Mailing.php
@@ -1305,6 +1305,7 @@ public function compose(
    * @param CRM_Mailing_BAO_Mailing $mailing
    */
   public static function tokenReplace(&$mailing) {
+    CRM_Core_Error::deprecatedWarning('function no longer called, use flexmailer');
     $domain = CRM_Core_BAO_Domain::getDomain();
 
     foreach (['text', 'html'] as $type) {
@@ -2475,7 +2476,7 @@ public static function delJob($id) {
    */
   public function getReturnProperties() {
     $tokens = &$this->getTokens();
-
+    CRM_Core_Error::deprecatedWarning('function no longer called - use flexmailer');
     $properties = [];
     if (isset($tokens['html']) &&
       isset($tokens['html']['contact'])
diff --git a/CRM/Utils/Token.php b/CRM/Utils/Token.php
index 050882216078..afe7784ba527 100644
--- a/CRM/Utils/Token.php
+++ b/CRM/Utils/Token.php
@@ -1183,6 +1183,7 @@ public static function getAnonymousTokenDetails($contactIDs = [0],
                                            $className = NULL,
                                            $jobID = NULL) {
     $details = [0 => []];
+    CRM_Core_Error::deprecatedFunctionWarning('function no longer used - see flexmailer');
     // also call a hook and get token details
     CRM_Utils_Hook::tokenValues($details[0],
       $contactIDs,
diff --git a/api/v3/Mailing.php b/api/v3/Mailing.php
index 6251b3840599..082a00a07654 100644
--- a/api/v3/Mailing.php
+++ b/api/v3/Mailing.php
@@ -501,60 +501,10 @@ function civicrm_api3_mailing_event_open($params) {
  * @param array $params
  *   Array per getfields metadata.
  *
- * @return array
  * @throws \CRM_Core_Exception
  */
 function civicrm_api3_mailing_preview($params) {
-  $fromEmail = NULL;
-  if (!empty($params['from_email'])) {
-    $fromEmail = $params['from_email'];
-  }
-
-  $mailing = new CRM_Mailing_BAO_Mailing();
-  $mailingID = $params['id'] ?? NULL;
-  if ($mailingID) {
-    $mailing->id = $mailingID;
-    $mailing->find(TRUE);
-  }
-  else {
-    $mailing->copyValues($params);
-  }
-
-  $session = CRM_Core_Session::singleton();
-
-  CRM_Mailing_BAO_Mailing::tokenReplace($mailing);
-
-  // get and format attachments
-  $attachments = CRM_Core_BAO_File::getEntityFile('civicrm_mailing', $mailing->id);
-
-  $returnProperties = $mailing->getReturnProperties();
-  $contactID = $params['contact_id'] ?? NULL;
-  if (!$contactID) {
-    // If we still don't have a userID in a session because we are annon then set contactID to be 0
-    $contactID = empty($session->get('userID')) ? 0 : $session->get('userID');
-  }
-  $mailingParams = ['contact_id' => $contactID];
-
-  if (!$contactID) {
-    $details = CRM_Utils_Token::getAnonymousTokenDetails($mailingParams, $returnProperties, empty($mailing->sms_provider_id), TRUE, NULL, $mailing->getFlattenedTokens());
-    $details = $details[0][0] ?? NULL;
-  }
-  else {
-    [$details] = CRM_Utils_Token::getTokenDetails($mailingParams, $returnProperties, empty($mailing->sms_provider_id), TRUE, NULL, $mailing->getFlattenedTokens());
-    $details = $details[$contactID];
-  }
-
-  $mime = $mailing->compose(NULL, NULL, NULL, $contactID, $fromEmail, $fromEmail,
-    TRUE, $details, $attachments
-  );
-
-  return civicrm_api3_create_success([
-    'id' => $mailingID,
-    'contact_id' => $contactID,
-    'subject' => CRM_Utils_Array::value('Subject', $mime->headers(), ''),
-    'body_html' => $mime->getHTMLBody(),
-    'body_text' => $mime->getTXTBody(),
-  ]);
+  throw new CRM_Core_Exception('This is never called because flexmailer intercepts it');
 }
 
 /**
diff --git a/ext/flexmailer/src/API/MailingPreview.php b/ext/flexmailer/src/API/MailingPreview.php
index 448f9b9c09ed..4d7fafbef188 100644
--- a/ext/flexmailer/src/API/MailingPreview.php
+++ b/ext/flexmailer/src/API/MailingPreview.php
@@ -3,7 +3,6 @@
 
 use Civi\FlexMailer\FlexMailer;
 use Civi\FlexMailer\FlexMailerTask;
-use Civi\FlexMailer\Listener\Abdicator;
 
 class MailingPreview {
 
@@ -33,11 +32,6 @@ public static function preview($apiRequest) {
       $mailing->copyValues($params);
     }
 
-    if (!Abdicator::isFlexmailPreferred($mailing) && empty($mailing->sms_provider_id)) {
-      require_once 'api/v3/Mailing.php';
-      return civicrm_api3_mailing_preview($params);
-    }
-
     $contactID = \CRM_Utils_Array::value('contact_id', $params,
       \CRM_Core_Session::singleton()->get('userID'));