I got a notice just now as part of my regular upgrade that it can also install 20.04. So I said ok, BUT...
Then I got the notice that this could take several hours. It does not say so but the implication is I won't be able to use my computer during that time. So my question is just to make that explicit, because if so, then clearly this install will have to wait until tonight.
Second, just a gripe / rant that I also got this report about literally hundreds of packages that are going to be removed - but there is no way to save the list for later review, which makes no sense to me.