Wp8.1gdr2 upgrade tutorial wp8.1gdr2 update method steps detailed

wp8.1gdr2 upgrade tutorial!
The wp8.1gdr2 upgrade tutorial is applicable to any WP device that cannot get the Win10 mobile version update, such as the Windows Phone model code-named "BUSH" in the figure below. Of course, Samsung and HTC's WP devices can also get GDR2 updates according to the method provided by WindowsMania.pl. Given that the Win10 mobile version of the system is still very unstable, this conservative update is not a desirable solution.

currently supports Win10 phone to update the preview version of the system models are as follows:
& middot; Lumia 1020
& middot; Lumia 1320
& middot; Lumia 1520
& middot; Lumia 520
·Lumia 525
·Lumia 526
·Lumia 530
·Lumia 530 Dual Sim
·Lumia 620
·Lumia 625
·Lumia 630< Br> ·Lumia 630 Dual Sim
·Lumia 635
·Lumia 636
·Lumia 638
·Lumia 720
·Lumia 730
·Lumia 730 Dual SIM
·Lumia 735
·Lumia 810
·Lumia 820
·Lumia 822
·Lumia 830
·Lumia 920
·Lumia 925
·Lumia 928
·Microsoft Lumia 430
·Microsoft Lumia 435
·Microsoft Lumia 435 dual card dual standby