It looks like Sony is doing a bang-up job in moving their smartphones to the latest version of Android. You can now add almost all of the Sony Xperia Z2 and Z3 smartphones to the list of Sony devices which are receiving the Android 6.0.1 Marshmallow update.
The OTA started pushing out for the Z2 and the Z3 series today, and only excludes the Z3 Compact Tablet. Here's a quote with more of the details,
"Today, build number 23.5.A.0.570 will begin furnishing a number of additional Xperia X2 and Z3 variants with Android 6.0.1 Marshmallow. Along with those aforementioned, the Xperia Z2 (D6502), Xperia Z3 (D6646, D6653), Xperia Z3 Dual (D6633), Xperia Z3 Compact (D5833) and Xperia Z2 Tablet SGP511, SGP512, SGP521) are now ready for the 900 MB bundle." ~ PhoneArena
Here are links to our dedicated sections for these phones: