British Airways Boeing 777-21H G-ZZZB operating the Muscat – Abu Dhabi sector of BA72 Muscat – Abu Dhabi – London Heathrow diverted via Al Ain this morning due to weather at Abu Dhabi. As a result crew did not have sufficient hours to reach London Heathrow and therefore the Abu Dhabi – London Heathrow sector diverted via Vienna for a crew change. The complete routing was Muscat – Al Ain – Abu Dhabi – Vienna – London Heathrow.