A Chinese developer just caught an interesting record in its server log, saying that a mysterious running Windows Phone OS version 8.10.12166 has downloaded his app. Considering the latest version of Windows Phone that we consumers have direct access to is 8.0.10328.78, the higher version in question has to be Windows Phone 8.1 being tested somewhere inside Microsoft.
Back in June, WMpoweruser reported sighting of Windows Phone version 8.10.12076.0, it's only natural that version number goes up in the past two months. Over the course, the developer of Chinese app Love Wallpaper HD has also caught glimpses of version number 8.10.12073.0, 8.10.12086.0, 8.10.12100.0 and 8.10.12102.0.
It's good to find Redmond hard at work polishing the next major system update. However, there's no word on when the update will come yet. It's widely believed that Windows Phone 8.1 has be postponed to early 2014. And by the pace of things (we are just beginning to get the GDR2 update), that expectation looks very true.