Thanks to the table_rewrite event, it is possible to implement a table rewriting policy only allowing the rewrite in maintenance windows.

Here's an example implementing such a policy.

CREATE OR REPLACE FUNCTION no_rewrite()
 RETURNS event_trigger
 LANGUAGE plpgsql AS
$$
---
--- Implement local Table Rewriting policy:
--- public.foo is not allowed rewriting, ever
--- other tables are only allowed rewriting between 1am and 6am
--- unless they have more than 100 blocks
---
DECLARE
 table_oid oid := pg_event_trigger_table_rewrite_oid();
 current_hour integer := extract('hour' from current_time);
 pages integer;
 max_pages integer := 100;
BEGIN
 IF pg_event_trigger_table_rewrite_oid() = 'public.foo'::regclass
 THEN
 RAISE EXCEPTION 'you''re not allowed to rewrite the table %',
 table_oid::regclass;
 END IF;
 SELECT INTO pages relpages FROM pg_class WHERE oid = table_oid;
 IF pages > max_pages
 THEN
 RAISE EXCEPTION 'rewrites only allowed for table with less than % pages',
 max_pages;
 END IF;
 IF current_hour NOT BETWEEN 1 AND 6
 THEN
 RAISE EXCEPTION 'rewrites only allowed between 1am and 6am';
 END IF;
END;
$$;
CREATE EVENT TRIGGER no_rewrite_allowed
 ON table_rewrite
 EXECUTE FUNCTION no_rewrite();