diff --git a/addons/purchase/models/purchase.py b/addons/purchase/models/purchase.py
index 5bfc7dfa788..3e7fa3907b5 100644
--- a/addons/purchase/models/purchase.py
+++ b/addons/purchase/models/purchase.py
@@ -1016,7 +1016,6 @@ class PurchaseOrderLine(models.Model):
             return
 
         # Reset date, price and quantity since _onchange_quantity will provide default values
-        self.date_planned = self.order_id.date_planned or self._convert_to_middle_of_day(datetime.today())
         self.price_unit = self.product_qty = 0.0
 
         self._product_id_change()
@@ -1071,7 +1070,7 @@ class PurchaseOrderLine(models.Model):
             params=params)
 
         if seller or not self.date_planned:
-            self.date_planned = self.order_id.date_planned or self._get_date_planned(seller).strftime(DEFAULT_SERVER_DATETIME_FORMAT)
+            self.date_planned = self._get_date_planned(seller).strftime(DEFAULT_SERVER_DATETIME_FORMAT)
 
         if not seller:
             self.price_unit = self.product_id.standard_price