Just comment that the Bluetooth.org (SIG) group has just certified some days ago the upgrade to KitKat for our Xperia M2 (and also for E1). Therefore, Sony might launch this long awaited update during this July hehe
On the other hand, I have spoken to Sony support's chat some hours ago for an issue of hardware, and I've also asked them if they knew what day it would be launched, but they have told me that they do not know that for sure, it will be soon, without giving details, what a pity! ..
Now we just have to wait