There are no deliveries scehduled for anything other than the A346. There is no reason why A340 FOs would move over to the B744; in fact, quite the opposite. As a result of the numbers of pilots moving from the B744 to the A340, there are the occasional courses for new pilots on that type. Whether you get on it is something of a matter of luck - pilots with both Boeing and Airbus histories have gone to the B744, but slots are few and far between.