android 4.4.4 kitkat update file s5 active G870A AT&T

how can i update my Samsung galaxy s5 active from at&t to the 4.4.4 android version in order to take it to lollipop since i have the update.zip to install it via recovery but it need the 4.4.4 version to get successfully install

S5 Active G870A OC5 root

Has anyone found a way to root the s5 active on oc5 build without it being previously rooted or downgrading to 4.4?