If i do the trip to birdsville, in 2 days, I plan to make it 4-5 hours past charleville on the first day. (26th) If the trip is done in three days, I think charleville would be a good stopover point on the first night (25th) then drive 10 hours or so the second day (26th), leaving a nice cruisy 6-7 hours to get to birdsville on the third (27th)
This leaves time to drink at the birdsville pub, o wait that's meant to be the return trip.
As for the return trip I am happy to go with the flow and head back at a cruisey pace with any others returning straight after the crossing.
Cheers