Update 7/9: Game of Thrones crew member Cat Taylor confirmed via Twitter yesterday (July 8, 2013) that filming did, indeed, start right on schedule.
Original article: It's hard to believe, but Game of Thrones Season 4 is already underway. The writers are hard at work crafting the scripts that will cover the second half of A Storm of Swords, and filming starts less than a month after the Season 3 finale.
In a recent interview with KCRW UpClose, which you can listen to below, Game of Thrones showrunners David Benioff and D.B. Weiss confirmed that filming for next season begins on July 8, 2013, which is why casting news is already leaking.
"Right now we're writing Season 4," they explained. "We start shooting July 8, and we have to have all 10 scripts ready before we start shooting, because we crossboard the entire season. So, scenes from the final episode might be shot the first week of production. And then we finish shooting, we go straight unto post-production, and also outlining the coming season."
Talk about a high-pressure job! It's a good thing the showrunners are so devoted to the source material — putting together something as epic as Game of Thrones requires a ton of passion.
Listen to the full interview below.