Update thread bumpable status and posts only if it is yet bumpable

boards/models/post.py

@@ -347,6 +347,7 b' class Post(models.Model, Viewable):'
 
         if self.id:
             for thread in self.get_threads().all():
+                if thread.can_bump():
                 thread.update_bump_status()
                 thread.last_edit_time = self.last_edit_time