The Xperia Z2, Z3, and Z3 Compact finally received Android Marshmallow over a week ago but only for those who took part in the beta testing phase. The Beta Marshmallow program for the models mentioned is now over and so Android 6.0.1 is now ready for almost all Z2 and Z3 users, specifically the D6503, D6603, D5803 variants of the Z2, Z3, and Z3 Compact, respectively. If you haven’t gotten a chance to download the fluffy Android, now is the time for you to taste and see what the Marshmallow can do to your device.
The Marshmallow firmware build number 23.5.A.0.570 for Sony Z2 and Z3 variants are now ready to be downloaded and installed. If you have an Xperia Z2 HSPA+,Xperia Z3 Dual, or Xperia Z2 tablet, you can get the update anytime now whether manually or over-the-air. Check if you receive an OTA notification or check manually on your device settings.
Android 6.0.1 Marshmallow (firmware 23.5.A.0.570) is now available for the following Sony Xperia mobile devices: Xperia Z2 (D6502, D6503), Xperia Z3 (D6603, D6646, D6653), Xperia Z3 Dual (D6633), Xperia Z3 Compact (D5803, D5833), and Xperia Z2 Tablet (SGP511, SGP512, SGP521). Some Marshmallow goodies that will be offered include notification changes, STAMINA mode, App Standby, Google Now on Tap, Sony Camera 2.0.0, app tray search option, and removal of option for classic and modern homescreen layout.
VIA: XPERIA Blog
Z2 D6503 but still no marshmallow love for it here (Romania). Checked both OTA and Sony companion pc app.