While some Sony Xperia owners are still waiting for the new Android Marshmallow OTA update to come to their devices, reports place Japanese versions of the current flagships to be making a leap to Android 6.0 soon.

According to Phone Arena, reports coming out of Japan suggested that Sony Mobile flagships, the Xperia Z4 (Xperia Z3+ outside Japan) and Z5, were already given WiFi certifications for Android 6.0.

The industry follower added that while components and features certification is just one process in a tech manufacturer's update to firmware and software versions, having one might mean that the whole process is already well on its way to being accomplished. This means that the Xperia Z4 and Z5 are already WiFi-certified for Android M, and the OTA rollout for Japanese versions of the flagships will be released soon.

The WiFi certification was released for major Japanese carrier models of the Xperia Z4 and Z5, such as DoCoMo. However, it is unclear if the WiFi certification also includes global versions of the devices.

Although Sony Mobile already confirmed that Android M will eventually release for the global, unlocked versions of Xperia devices, there are no definite dates yet when the base version Android 6.0 will be rolled out. The latest off the rumor mills suggested that the global versions of Sony Xperia Z5 will make the jump to Android 6.0 in the early months of 2016, possibly as early as January.

While there are still no confirmed details about the Android 6.0 switch for Xperia devices, the company did set up on its developer's site a process with which the more tech-savvy owners can test out beta versions of Android Marshmallow. The Android 6.0 Concept files for test users on Xperia Z3, Z3+, and other Xperia devices can be found on the website.