My UK visa expires soon, what should I do now during the COVID-19 outbreak? [closed]

I am a Brazilian citizen actually traveling and volunteering in the UK (been here for 5 months).

I came with a normal visa plus the return ticket (in April 21st). Right now I'm in Scotland's highlands (this is relevant because I would have to travel quite a bit to get the flight). I can switch to any flight until December 31st.

My flight back goes through London, Lisboa and then Brazil. This is troublesome as Lisboa border will potentially close. I can think of 3 scenarios:

1. flight goes well and get home (sounds easier than it will be)
2. flight cancelled and postponed for a date after my visa expires
3. Flight-on-date but I don't take the flight to take care of my health and see how this situation evolves.

The question boils down to:

• Is there any way to extend my visa or: is it too bad to stay longer and let it expires?

(I've tried to contact a few governmental entities with no response so far, which is reasonable as they might be overloaded).

Disclaimer

As I've said on the bottom of the post, I emailed the embassy. They only replied today and the link they sent points to uk advices for chinese people, and it's completely useless. As I was expecting the flight state is rather uncertain (tap air portugal). You can check the cancelled flights. I would also recommend anyone having a safe chance to go back to do it. This is not the case.