I would say region 10 would be next since the reward for completing the pistol events were region 10 guns. As to when, whenever Glu decides to announce it.
Reading the "new update" thread I'd say Glu will be working with the Android users that lost all of their game data trying fix the zombie glitch they had....until region 10, have fun with the Oxford and completing the "bounties" section.
Comments
Zombies just came out today in the latest game update. Download update and check out pistol series in regions 7 and 9.
Download the update. Then go to regions 7 and 9.