According to The Wrestling Observer, WWE had been planning to spend the next few months building Roman Reigns up with the idea that he would win the Royal Rumble and go on to challenge for the WWE World Heavyweight Title at WrestleMania 31. He will be out of action for a few months but even in a worst case scenario, Reigns should be back in time for the Rumble and plans may not be changed that much.
With Reigns out, it appears that Dean Ambrose will be getting the push as the number 2 babyface for now.
Reigns and Daniel Bryan should both be back at around the same time. Another Superstar expected to be back for WrestleMania 31 season is Batista, possibly doing his farewell run.