Another data point:

Called Finnair yesterday and today.

Reroute to BKK would cost extra. I said never mind.

Ticket can't be extended after 31st of November. I explained that HK will closed for the rest of year with the passport I hold. After checking this, he send an e-mail to back office. Next day called back to hear that back office said no. Only refund. I told them Flugladen.de (I know, never again) doesn't respond to the 10 e-mails already, so can't cancel at the moment. Finnair said they had more complaints. I have to wait and see what happens. If the flights get cancelled by AY again, then I can rebook into 2021. Of not, I call them a few days before and they will see to override to cancel and refund straight from AY to myself.