diff --git a/application/forms/EscalationConditionForm.php b/application/forms/EscalationConditionForm.php
index 96b6b51d..f4981250 100644
--- a/application/forms/EscalationConditionForm.php
+++ b/application/forms/EscalationConditionForm.php
@@ -257,7 +257,7 @@ protected function handleRemove(): void
             unset($this->options[$toRemove]);
 
             if ($this->deleteRemoveButton && count($this->options) === 1) {
-                $key = array_key_last($this->options);
+                $key = key($this->options);
                 $this->options[$key]->remove($this->getElement('remove_' . $key));
             }
         }
diff --git a/application/forms/EscalationRecipientForm.php b/application/forms/EscalationRecipientForm.php
index 006d71a8..28b7a6c0 100644
--- a/application/forms/EscalationRecipientForm.php
+++ b/application/forms/EscalationRecipientForm.php
@@ -224,7 +224,7 @@ protected function handleRemove(): void
             unset($this->options[$toRemove]);
 
             if (count($this->options) === 1) {
-                $key = array_key_last($this->options);
+                $key = key($this->options);
                 $this->options[$key]->remove($this->getElement('remove_' . $key));
             }
         }
diff --git a/application/forms/SaveEventRuleForm.php b/application/forms/SaveEventRuleForm.php
index f19f25b1..64c68e7a 100644
--- a/application/forms/SaveEventRuleForm.php
+++ b/application/forms/SaveEventRuleForm.php
@@ -413,7 +413,7 @@ public function editRule(int $id, array $config): void
             });
 
             if ($escalationInCache) {
-                $position = array_key_first($escalationInCache);
+                $position = key($escalationInCache);
                 // Escalations in DB to update
                 $escalationsToUpdate[$position] = $escalationInCache[$position];
                 unset($escalationsInCache[$position]);
diff --git a/library/Notifications/Widget/EventRuleConfig.php b/library/Notifications/Widget/EventRuleConfig.php
index 1ae0a4f9..5adc36bc 100644
--- a/library/Notifications/Widget/EventRuleConfig.php
+++ b/library/Notifications/Widget/EventRuleConfig.php
@@ -83,7 +83,7 @@ protected function createForms(): void
 
         $addEscalation = (new AddEscalationForm())
             ->on(AddEscalationForm::ON_SENT, function () use ($escalations) {
-                $newPosition = (int) array_key_last($escalations) + 1;
+                $newPosition = count($escalations) + 1;
                 $this->config['rule_escalation'][$newPosition] = ['id' => $this->generateFakeEscalationId()];
                 if ($this->config['conditionPlusButtonPosition'] === null) {
                     $this->config['conditionPlusButtonPosition'] = $newPosition;