diff --git a/addons/stock/models/stock_move.py b/addons/stock/models/stock_move.py
index 26db3fa010f..a5b97bc7938 100644
--- a/addons/stock/models/stock_move.py
+++ b/addons/stock/models/stock_move.py
@@ -283,7 +283,7 @@ class StockMove(models.Model):
                     if propagated_date_field:
                         current_date = datetime.strptime(move.date_expected, DEFAULT_SERVER_DATETIME_FORMAT)
                         new_date = datetime.strptime(vals.get(propagated_date_field), DEFAULT_SERVER_DATETIME_FORMAT)
-                        delta = new_date - current_date
+                        delta = relativedelta.relativedelta(new_date, current_date)
                         if abs(delta.days) >= move.company_id.propagation_minimum_delta:
                             old_move_date = datetime.strptime(move.move_dest_id.date_expected, DEFAULT_SERVER_DATETIME_FORMAT)
                             new_move_date = (old_move_date + relativedelta.relativedelta(days=delta.days or 0)).strftime(DEFAULT_SERVER_DATETIME_FORMAT)