you need to differentiate between training like Flybe are doing (that is not the norm)
How is it not the norm?
If you look at where they have been all of the airfields would be logical options for them to operate into / out of.
And there are places they haven't been that would be just as logical - Southampton for instance.... And I doubt whether anywhere is so busy that they'd be turned away. Is there anywhere at the moment where there isn't "bugger all else going on"?
And maybe that's what they want everybody to think. Maybe it's the old magicians trick - when they are telling us to look left, we should be looking right