Nokia Lumia 520( cyan) : Airplane mode stuck and rapidly switching on and off

Find my details:-

software: windows phone 8.1

OS version: 8.10.12393.890

Firmware revision number: 3058.50000.1525.0001

Hardware revision number: 1.5.0.1

radio software version: 2.0.242037.8

chip SOC version: 8227

Extras+info

Lumia cyan

Device activation client 1.4.2.9

Firmware Updater Notifier 1.1.03

..... and so on

Manufacturer:-

RM-914_im_india_269

I was using Lumia Black and updated it to 8.1 ( Cyan) from my phone itself ( official release). I updated to Cyan OS not longer than a month back. Everything was fine, until recently, a couple of days earlier, when I was talking to a freind of mine on my phone, the call dropped. A notification to restart my phone appered so I did it. Ever since I am stuck on the , " Airplane mode". The flight mode will rapidly switch on and off. So, I am unable to use my Sim and thus, no whatsapp, no calls..social life has been paralyzed. 

I tried Hard reset ( about menu-> reset your phone) :- three times

Soft reset:- several times

Changed SIM :- a dozen times

Tried the twitter team suggestion ( I had found on this forum itself :- http://discussions.nokia.com/t5/Nokia-Lumia/Lumia-1520-3-and-official-8-1-stuck-airplane-mode/td-p/2855086)

Now trying Nokia Software Recovery Tool 1.5.0 but the problem is that it is downloading 3058.50000.1425.0001, which I beleive is 'Cyan' again. I am also worried, I won't be able to downgrade to Lumia black  which I am missing a lot. Anwho, I am  currently downloading it and will see what happens, but If Nokia's Technical team can provide a solution for this software/firmware related glitch, I will be a happy fella. I am wondering, about the first occurence of this problem which I researched as being reported on Nokia official forums, 2-3 months back. By now a trustworthy solution should have been found and posted online.