Power cuts are expected in the UK. Of course the government are blaming the fact that everyone is at home for this but in reality everything has been fine for a week so why it should change now is uncertain. Probably the government flexing their muscles and doing some more scaremongering. So if all channels go offline, this could be why. Read more on this on the search engines.
Internet outages are rumoured to occur in the coming days. This is related to China and the USA blaming each other for the virus.
The official reason that internet outages might happen is because everyone is at home using the internet. But as with the power cuts, everything has been fine for a week so why it should change now is not clear.
The unofficial rumours are that massive digital attacks are expected to take place across the globe which could bring the internet down. Possibly also that governments will shut down the internet intentionally to keep rumours (or the truth) from circulating.
If one of these countries has in fact launched an attack on the other by releasing the virus intentionally, then it's understandable that instead of annihilating the world with nuclear weapons, that a digital war will ensue, along with the usual trade sanctions / embargo etc. The next generation of war might be economic warfare, attacks on digital infrastructure and networks, and terrorism. You can read more about that here
China is known for computer hacking attempts worldwide but also the USA has a mass of resources which could be utilised. DDOS attacks ( Distributed Denial of Service - a term for when hackers take websites offline at will ) have happened for decades, even some of the biggest websites have been taken offline by a disgruntled hacker. If an angry teenager can take a website offline then imagine what a group of the world's most highly skilled hackers working for a government is capable of. So if our website or all channels are offline then you will know why. Actually saying all this, if our internet goes down then yours possibly will too so perhaps you won't even notice.
Some countries are already without internet. You can Google "internet shutdown covid-19" for more on this.