Original itinerary LAX-JFK-DOH (Doha)-DPS (Denpasar) 001 ticketed, all on AA flight numbers but the flights are a mixture of AA & QR metal. QR have cancelled the JFK-DOH leg and AA have auto rebooked on an itinerary departing LAX the following morning which gets me into DPS 18 hrs late and includes a 8.30hr layover in DOH instead of the previous 2hrs 15 layover.

I'm constrained in bringing forward my departure day and time from LAX due to existing commitments (I can't depart LAX before 21:00hrs on the planned date)

Looking at schedules there are alternatives which would significantly reduce the disruption to me including:

LAX-HKG-DPS leaving LAX 90 minutes later than originally planned but getting me into DPS 5 hrs early. This is available right through with AA flight numbers although CX operated.

LAX-LHR-DOH-DPS which would leave LAX 25 minutes earlier than originally planned and connect me in DOH onto my original DOH-DPS flight and therefore arrive as originally planned. However from what I can see although AA codeshare with QR LHR-DOH I can't find a AA flight number on the last QR LHR-DOH flight of the day so that leg may need to be on a QR flight number.

What can I ask AA reservations to do and how flexible are AA reservations likely to be in changing me to either of the 2 alternatives above instead of the proposed original routing rebook which would means a 18 hour delay in arrival?