diff --git a/tests/units/UserEscalationTest.php b/tests/units/UserEscalationTest.php
new file mode 100644
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--- /dev/null
+++ b/tests/units/UserEscalationTest.php
@@ -0,0 +1,98 @@
+<?php
+
+/**
+ * -------------------------------------------------------------------------
+ * Escalade plugin for GLPI
+ * -------------------------------------------------------------------------
+ *
+ * LICENSE
+ *
+ * This file is part of Escalade.
+ *
+ * Escalade is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Escalade is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Escalade. If not, see <http://www.gnu.org/licenses/>.
+ * -------------------------------------------------------------------------
+ * @copyright Copyright (C) 2015-2023 by Escalade plugin team.
+ * @license   GPLv2 https://www.gnu.org/licenses/gpl-2.0.html
+ * @link      https://github.com/pluginsGLPI/escalade
+ * -------------------------------------------------------------------------
+ */
+
+namespace GlpiPlugin\Escalade\Tests\Units;
+
+use GlpiPlugin\Escalade\Tests\EscaladeTestCase;
+use PluginEscaladeConfig;
+
+final class UserEscalationTest extends EscaladeTestCase
+{
+    public function testTaskGroupEscalation()
+    {
+        $this->login();
+
+        $config = new PluginEscaladeConfig();
+        $conf = reset($config->find());
+        $config->getFromDB($conf['id']);
+        $this->assertGreaterThan(0, $conf['id']);
+        $this->assertTrue($config->update([
+            'remove_tech' => 1
+        ] + $conf));
+
+        $user1 = $user2 = new \User();
+        $user1->getFromDBbyName('glpi');
+        $this->assertGreaterThan(0, $user1->getID());
+        $user2->getFromDBbyName('tech');
+        $this->assertGreaterThan(0, $user2->getID());
+
+        $ticket = new \Ticket();
+        $t_id = $ticket->add([
+            'name' => 'Task User change Escalation Test',
+            'content' => '',
+            '_actors' => [
+                'assign' => [
+                    [
+                        'items_id' => $user1->getID(),
+                        'itemtype' => 'User'
+                    ]
+                ],
+            ]
+        ]);
+
+        $ticket_user = new \Ticket_User();
+        $this->assertEquals(1, count($ticket_user->find(['tickets_id' => $t_id, 'type' => \CommonITILActor::ASSIGN])));
+
+        // Update ticket with just one group
+        $this->assertTrue($ticket->update(
+            [
+                'id' => $t_id,
+                '_actors' => [
+                    'assign' => [
+                        [
+                            'items_id' => $user1->getID(),
+                            'itemtype' => 'User'
+                        ],
+                        [
+                            'items_id' => $user2->getID(),
+                            'itemtype' => 'User'
+                        ]
+                    ],
+                ],
+            ]
+        ));
+
+        $ticket_user = new \Ticket_User();
+        $user_linked = $ticket_user->find(['tickets_id' => $t_id, 'type' => \CommonITILActor::ASSIGN]);
+        $this->assertEquals(1, count($user_linked));
+        reset($user_linked);
+        $this->assertEquals($user_linked['id'], $user1->getID());
+    }
+}