Microsoft recently launched Windows Phone 8, but existing devices will not be updated to Windows Phone 8, instead they will get updated to Windows Phone 7.8, and many people had thought that this would be the last software update for these devices.
Now it would appear that Windows Phone 7 devices will be updated beyond Windows Phone 7.8, possibly Windows Phone 7.9, as details have appeared online of a future Windows Phone update beyond 7.8 which is currently listed as 7.x.
There are no details as yet on when this new Windows Phone 7.x update will be available, although we suspect it will be a while as Microsoft has yet to release the Windows Phone 7.8 update.
Source WPArea.de, WMPoweruser