As I just mentioned it happens to me and some of the other players living in UK. If it was basic cookie or browsing history issue it wouldn't occur on multiple different browsers.

Also if you actually research the Error 504 you will find that 99% of the time it's issue between servers and generally have nothing to do with end user.

I appreciate your attempt to help as always, but once again all this issue requires is a developer to get off his lazy ass and do some research.