https://github.com/apache/airflow/pull/12139 added some new params to the scheduler -- we have "cursory" docs for them in the comments in the config file, but we should have a more details docs in the scheduler.rst page.
airflow/jobs/scheduler_job.py
self.log.warning(
                        "Task %s doesn't exist in DAG anymore, skipping SLA miss notification.", sla.task_id
                    )
                    continue
                tasks_missed_sla.append(task)
            emails: Set[str] = set()
            for task in tasks_missed_sla:
                if task.email:
                    if isinstance(task.email, str):
                        emails |= set(get_email_address_list(task.email))
                    elif isinstance(task.email, (list, tuple)):
                        emails |= set(task.email)
            if emails:
                try:
                    send_email(emails, f"[airflow] SLA miss on DAG={dag.dag_id}", email_content)
                    email_sent = True
                    notification_sent = True
                except Exception:  
                    Stats.incr('sla_email_notification_failure')
                    self.log.exception("Could not send SLA Miss email notification for DAG %s", dag.dag_id)
            
            if notification_sent:
                for sla in slas:
                    sla.email_sent = email_sent
                    sla.notification_sent = True
                    session.merge(sla)
            session.commit()
    @staticmethod
    def update_import_errors(session: Session, dagbag: DagBag) -> None: