It happens w/ a lot of cartoons, Steven Universe was pretty notorious for it at one point and there were several notable instances of it happening with Adventure Time, too (although I suspect in those cases it was more to do with Cartoon Network hanging onto the eps for months and not communicating with their overseas counterparts >_>). And don't even get me started on how often it happens with Nickelodeon shows...
I hope nothing too major/spoilery/whatever airs overseas :O I know it's a pain to avoid spoilers when stuff like this happens.