I have a flight booked for next year (as part of a great fare I picked up flying YVR-DPS on JL) flying a GA domestic business class flight DPS-CGK. The flight is booked leaving DPS at about 9.30pm and arriving around 10.30pm and we have a flight the next day CGK-NRT-YVR with JL at around 6.30am. It would be much better if we could pick up an earlier flight from DPS-CGK to get a longer overnight layover in CGK. GA usually run at least 10 flights a day from DPS-CGK so they should have availability (in theory). Does anyone have any experience of trying to get on an earlier flight with GA? If there is availability, are they happy for you to fly ahead?