Let's start with advising you to take this following rumor with a Fortress of Solitude-sized grain of salt until official word comes from Warner Bros, or Director Zack Snyder, but in the meantime for this sake conversation...
Rumor that Batman V Superman Dawn of Justice might be split into two parts starting with Part 1: Enter the Knight? and Part 2: Dawn of Justice? With Movies coming into 2015, this one is a total rumor. Oct. 23, 2015 Enter the Knight could be released? And Dawn of Justice to be released March 25, 2016? I mean come on Warner Bros, make your decision if you want it to be split into 2 parts. Picture above, Ain't It Cool News came across the image above yesterday that was allegedly snapped from the end of the upcoming Batman v Superman teaser trailer, which is reportedly attached to the February 6th screening/released of Warner Bros, Jupiter Ascending.
As Ain't It Cool News points out: ''Giving Batfleck something of an 'intro' movie would allow the character to breathe before pitting him against Henry Cavill's Kal-El, and would establish him as his own entity in this rapidly expanding universe. Then again, the idea of them finishing up their work 5 month ahead of the previously-announced schedule seems... outlandish at best, unless there was some serious, SERIOUS prioritizing on the VFX/editing font.''
It should be noted that Justice League is already set to be released as a two-part movie, a trend that's all the rage with studios these days. If this is real or a rumor, to be legit then you are happy to see Batman V Superman split into two movies!
UPDATE: Henry Cavill says that Batman V Superman Won't be split into 2 movies.