But a new image alleged to be that of the Sony Xperia Z1s, found on a Chinese web site, shows that the device is actually larger when standing next to the Xperia Z1. One major physical difference that we can see from the picture below is that on the Xperia Z1s the 3.5mm earphone jack is nearly centered on top of the device as opposed to its placement on the edge of the Xperia Z1. The earphone placement matches an earlier leak of the Sony Xperia Z1s from evleaks.
So the bottom line is that the phone we've known as the Sony Xperia Z1s might actually be a Sony Xperia Z1 Max . That would mean that somewhere at Sony lies a phone with the specs that we've attributed to the Xperia Z1s and whose name we do not yet know.
Sony Xperia Z1s could be the Xperia Z1 Max
source: Digi-Wo (translated), XperiaBlog via TechRadar