According to The Wrestling Observer, the plan remains for Brock Lesnar to win the WWE World Title at some point, and there has been talk of him defending the title against Roman Reigns at WrestleMania 31.

We have also confirmed that Lesnar will be working SummerSlam this year (where he will likely win the title) and the Night of Champions PPV which follows SummerSlam.

As far as when Brock Lesnar's WWE return will take place, there have been rumors he will make his return at Battleground, to put Triple H's "Plan B" in motion against John Cena.

Aside from all the above, little is known as to how many events Lesnar will be working beyond Night of Champions. There has been talk of him working Royal Rumble next year, but for him to carry the title from SummerSlam through WrestleMania 31 would mean he'd have to work a lot more dates than he typically works on his part-time schedule.

Oh lord... He's going to say "Plan B... B as in Brock" isn't he?

SummerSlam to WrestleMania 31 is too far of a gap, I don't think Brock would want to hold it on that long, knowing that he's only a part-timer.

^
lol like he gives a shit. He'd hold a bag of crap for that long as long as he's getting paid.

I don't want it on a par-timer that long, though. The World Champion should be on the show every week and he wouldn't be.