Originally Posted by
tauphi
It's just a courtesy and not required. Most people who fly early will end up in China and I doubt they're going to be bothering with following up each individual case with prosecution that will simply go nowhere. This is no different with the earlier 7+7 system where you could leave during the +7 period and skip the mandatory PCR testing.
It's more than a courtesy if you are HK resident and plan to ever return in the future.
Apparently, all those missing compulsory PCR are flagged and receive a 10,000 fine plus a nasty letter a few weeks later (usually delivered by the police)..