Bugging in is much easier. You don't have to carry stuff.

When bugging out you have to decide where to go. I guess if you have two homes, then in a crisis you might prefer to be in the other one. If I'm at work I'll probably want to go home, which is a 3-mile walk.

If I'm at home, then I'll only want to relocate if I have no choice, and then I'd hopefully have more information. A lot depends on how many other people are affected. A tornado here is liable to affect fewer than 50 houses, so I can just move into a hotel if mine is one of them. With a national disaster, anywhere I could reach would already be full of other refugees. Britain is a small country; it's not like America or Europe where it seems you have unlimited land you can walk to.

Leaving this island by boat, plane or chunnel would have to be done well in advance to avoid the crowds.