Windows Phone 8.1 aka Windows Phone Blue already being tested on Lumia 920 and test devices.

Third teaser from Alan@Adduplex reveals that Windows Phones’s next iteration “Windows Phone Blue” aka WP8.1 is already getting tested on test devices P4301 and Lumia 920.  This is quite early as Windows Phone Blue is supposed to come early next year. Current devices will be treated to upcoming GDR2 and GDR3 before finally hugging WP8.1.

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