Sai is this month's sign in reward, last month was suppose to be Sakura but they changed to Ino. We got Choji a couple months ago so I doubt we will get hime again. It will most likely be Sakura her bio says sign in rewards and she's the only one in the current game we don't have. I doubt they'd double up so soon I mean I haven't seen GNW kbia since I first started playing almost a year ago.