In the alleged FCC listing, it points to a model with type number PM-0851-BV, acknowledging the presence of a Dual SIM slot. This document claims that the only hardware difference would be the inclusion of an additional SIM socket. In the past week, there was an FCC listing for a particular PM-0850-BV, which many have believed it to be the upcoming Sony Xperia Z4. Not only that, this device did receive its certification in Japan not too long before that.
We do hope that there will be a whole lot less grasping of straws at the moment, and more concrete information for us to fall back on in the near future. After all, with Mobile World Congress coming up soon, hopefully we will be able to see the Xperia Z4 unveiled then – whether in Dual SIM glory or not.