Look what we found! The most recent known version of Windows phone 8.1 is 8.10.14157.200 and it comes with the update to Windows Phone 8.1 update1 aka GDR1.
Now, a much more advanced Windows Phone 8.1 has revealed itself at WP Bench. The version number in question is 8.15.12375.0 which marks a big jump in the version number over 8.10.14157.200. We already told you that GDR2 of Windows Phone 8.1 may pack new hardware support and many new features.
While with cancellation of McLaren, the new hardware support may not be urgently needed, but the jump in version does confirm that it will come with lots of changes.
The GDR2 dev preview has been marked for October by our sources, but don’ get surprised if it happens sooner than that.