Lancastrian instead of York
I believe this is a Lancastrian service (the types were not shown) from a June 1946 timetable in my collection.
London : 1145 Tu
Lydda : 0200/0400 We
Karachi : 1530/1730 We
Singapore : 0930/1130 Th
Darwin : 2300/0130 Fr
Sydney : 1030 Fr
Three times a week departing Tuesday, Thursday and Sunday. You would need at least four aircraft to maintain the schedule. For the times, these seem some very long nonstop legs, and indeed a very fast trip to Australia. I would guess the York couldn't have made those sectors.