Unabungler, I am surprised at the content and lack of knowledge in your posting.
It appears you are not aware that Virgin Atlantic (VS) offer 3 departures per day between LHR and SIN using a code share arrangement in economy only with SQ.
If you wander out to SYD International you will see a daily VS arrival from KUL. Yes, VS have a code share with MH between KUL and SYD. Any VS pax for SYD from LHR travel from LHR to KUL on the VS a/c and transfer to a MH a/c for the last sector to SYD.
When AN operated to HKG there was an arrangement between AN and VS. Large numbers of pax travelled SYD to LHR over HKG using AN and VS. With the demise of AN my guess is that VS are missing the business in the downturn.
Your statement 'the VERY lucrative Kangaroo route' will have management and most crew rolling in the aisles. You may be surprised to learn that some fares from S.E Asia to LHR are more expensive than from some Aust Ports.
There may be some surprises in store from AN regarding international services after the 1st Feb. All the AN international traffic rights including those to the U.K via both SIN and BKK have been retained.