I’m not sure how anyone is going to do any work if they do!
This.
I expect lots of individual, repeat closures, as and when cases come to light, to the point that at some point most schools are closed. I don't expect a blanket closure.
I am lucky that I can work from home and have an understanding manager - I can change hours and take time off at short notice and do my hours at antisocial times if I need to. I don't see how people who can't work from home, and have to give notice of changes will be able to manage individual, short-notice closures. Not to mention the impact on education.
Oh and bubbles of 90 and 180 are a bloody joke.