Besides those terms, what about spelling? I didn't notice any but I wasn't really paying attention either. Colour instead of color and that sort of thing. Those are the kinds of differences that someone would usually make without thinking about it and be more likely to reveal their origin than a few important terms that they could just look up.
Also, as far as time zones are concerned, if the update gets released when it is July 1st in England but it is still June 30th in the U.S. what the game developer says about the date when he posts the update might be an indication of which country/time zone he is in.
Of course, it would be better for us if he was in England or Australia or anywhere further ahead in time than the U.S. since that would mean that he would finish the game comparatively early on whichever day he actually releases it.