After I checked the events of "Hub Interview" by Region, I found in China one interview located Beijing has been set down, but no such event in Shanghai. I heard some applicants from Beijing got good news but no one got in Shanghai. Does it mean that outside US, only after adcom set down logistic issues for a regional hub, the interviews for such place will be issued out?
Adcom at Wharton (other schools may have different policies) process applications and thus issue invitations purely as they come out of the stack of files.
The timing of issuing invitations has absolutely nothing to do with the timing of hub interviews. Adcom do NOT sort through applications looking for, say, applicants near Beijing, or hold back applicants near Shanghai.
Relatively few invitations (to anyone) have gone out yet, so it is not surprising that the intersection of a small number of invitations and your personal network of MBA applicants in Shanghai is currently zero.