All good mate.  No warning at all.  I was halfway through adding a few fire hydrants, searched a local street a few kilometres away, and ended up at an identical street in the UK.

I backed out and headed back to NZ, but must have likely moved something by accident on the way.

No warning at all.  It probably incremented the number of edits, but as I was halfway through, wouldn't have noticed.

I've analysed it, but can't really think of any way to prevent it happening again.  I consider myself very careful, but I missed this one.

Usually I'd get back to NZ by hitting the GPS location icon, but I haven't been able to get it to work in this browser.  I might have another look at that.  

Or, reverse my last edit, that'd take me home.

Luckily, my error was swiftly noticed and rectified.  The system works!

Au revoir!  ;-)