Okay... now we have an advance screening to the world premiere, occurring in China on June 13th - five days before the "Worldwide (except China) Premiere" in London.

This is the same city as the fan-vote, so June 13th must be the date of the 10th Anniversary Fan Event, culminating in an advance screening of the Movie.
Fans in China have a chance to be at the screening, by submitting an essay about their favourite Transformers characters.