Update project_task.py

custom_project/models/project_task.py

@@ -55,8 +55,10 @@ class ProjectTask(models.Model):
 
     def write(self, vals):
         if vals and type(vals) == dict:
-            if vals.get("x_start_date") or vals.get("x_end_date"):
-                for rec in self:
+            for rec in self:
+                if vals.get("x_start_date"):
                     rec.planned_date_begin = datetime.combine(rec.x_start_date, datetime.min.time()) + timedelta(hours=15)
+                        
+                if vals.get("x_end_date"):
                     rec.date_deadline = datetime.combine(rec.x_end_date, datetime.min.time()) + timedelta(hours=12)
         return super().write(vals)