FWIW with reference to the above the SIN situation changed very rapidly in Feb/March, certainly for flights to/from the UK/Oz..
Start of Feb it was temperature checks in the terminal..that was pretty much it..
8 weeks later no passengers were being allowed off the aircraft, (i.e; transit pax bound for Oz stayed on board), crew, who had to diesembark for flight time limitation reasons, were locked in at airport hotel...
Yes, the UK approach was (and perhaps still is) astonishing.
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