Allylic bromination with NBS

I know that NBS is a selective brominating agent especially on the **allylic position**. And its reaction mechanism is of free radical.


But I can't figure out the reason for the change in position of the double bond in the products.


It would be helpful if someone could give the mechanism along with its reason.


[![reaction of 4,4-dimethyl cyclohexene with NBS at its respective allylic positions (A)and(B)](https://i.stack.imgur.com/UEaDw.jpg)](https://i.stack.imgur.com/UEaDw.jpg)


This is what I'm thinking, that might be happening there but still I don't understand how and why something like this would happen.


[![for A](https://i.stack.imgur.com/lVu6U.jpg)](https://i.stack.imgur.com/lVu6U.jpg)
[![for B](https://i.stack.imgur.com/XLhlS.jpg)](https://i.stack.imgur.com/XLhlS.jpg)


My mistake, number 3 and the product which I have marked as not formed are same.


2)**Which one among these three products is the *major product*?**


