Yeah and thats the right place to put it, at random spot on the back.. its stupid
I doubt that anything with Windows10 will be called x30/1530. They normally increment the number by 20 when they switch to a new OS (e.g. L900 with WP7 and L920 with WP8). My guess is the Windows10 phones will all be x40/1540
Hold a Lumia 1520 and see where your index finger will be!