Take this with a grain of salt, since it's not an official Warner Bros. source--but BeInAMovie.com is claiming that in less than a month, Zack Snyder will begin filming crowd scenes for Batman vs. Superman next month.
Batman-News reports that this is the same company that put out similar casting calls for The Dark Knight Rises, which included the huge extras call for the football stadium scene.
"October seems early to me, especially since we heard that they’ll be kicking off production in February 2014 in Detroit," that site reports. That's more or less what the rest of us heard, too, and considering that set photos are beginning to leak of Henry Cavill in The Man From U.N.C.L.E., it seems likely any potential filming for the Man of Steel sequel will be simply coverage shots--generic city images with crowds of extras reacting to...something, or some other scene that doesn't require the presence of the lead.
Be In A Movie is recruiting for extras to be filmed somewhere in Los Angeles on October 19th, from 5:00 pm to 10:00 pm.