single -

app/models.py

@@ -132,7 +132,7 @@ class School(AbstractBaseUser, PermissionsMixin):
 
     def updateTeam(self):
         with transaction.atomic():
-            identifier = f'{Edition.current().year}-{self.id}'
+            identifier = f'{Edition.current().year}-{self.id}-'
 
             Student.objects.filter(identifier__startswith=identifier).update(
                 school_name=self.name,