diff --git a/src/RRule.php b/src/RRule.php
index f6f7b38..6fa6286 100644
--- a/src/RRule.php
+++ b/src/RRule.php
@@ -118,7 +118,7 @@ public function startAt(DateTimeInterface $start): self
             $startDate->setDate($now->format('Y'), $start->format('m'), $start->format('d'));
         }
 
-        $this->rrule->setStartDate($startDate, true);
+        $this->rrule->setStartDate($startDate);
 
         return $this;
     }