The Android 6.0 Marshmallow, the latest edition of Android OS was launched in October last year. Motorola, LG and HTC have already started rolling out Android 6.0 upgrade for their smartphones. However, Sony has still not released Android M update for its flagship smartphones.

According to Mobi Picker, Sony was expected to release Android 6.0 Marshmallow upgrade for its Xperia Z series smartphones in this month. However, it has only managed to release a concept beta version of the update to select smartphones like Xperia Z3 and Xperia Z3 Compact.

Fresh information suggests that none of the eligible Sony Xperia smartphones will be receiving Android 6.0 upgrade in this month. The Marshmallow update has received certification from Wi-Fi alliance for devices like Sony Xperia Z5 and Xperia Z4 smartphones.

The publication has reported that Sony will be releasing Android 6.0 upgrade for Xperia smartphones in the middle of the next month. The Sony Xperia Z5, Z5 Premium and Z5 Compact smartphones will be the first smartphones to get Android 6.0 in the coming month.

The Xperia Z3 smartphones are also likely to receive Android M update in February as Sony is testing beta edition of Android 6.0 with over 10,000 users of Xperia Z3 and Z3 Compact smartphones spanning across multiple countries in the Europe.

The Sony Xperia Z3+ and Z2 owners are also expected to receive Android 6.0 update starting next month. The non-Xperia Z series smartphones M4 Aqua, Xperia M5, Xperia C4 and Xperia Z5 are all Android M eligible devices that are poised to receive upgrade soon.

At the beginning of this month, it was reported that event tablets like Sony Z3 Tablet and Xperia Z2 Tablet will also receive Android 6.0 upgrade. The older Sony Xperia Z Ultra Google Play Edition smartphone from 2013 will also be updated to Android M.