Any metod to update H950 ATT To 5.1.1?

I Have H950 G Flex2, But i didnt get android 5.1.1 , i love this phone even it get hot somethimes, its good for me.
I want to know if maybe someone can help me to update to 5.1.1 because i dont have ota Update avalible and if is possible, try a stock or international room of 5.1.1 for the H950 Because att have a lot of bloatware.

Thanks all!