@kev holy s***, that's insane. At least you know they definitely don't know where you live! But also they might stay on the lookout in that area for a while on the presumption it's your usual route, so maybe hold off from taking it back out a while?

Not that you should have to, but safety first and all that.

Also maybe get a tracker fitted and if it does happen again, let them take it. Better to keep your life than the bike and between a tracker and insurance you'd get it back anyway.