Dude its was double xp for like 4 days people grind it so hard my mate is 9th the other is 10th if you play S&D and are good you go by so fast.

Im 5th and I played it quite a bit.

No, they are not glitching or hacking or anything among that.

I have 2 days and like 4-5 hours played of in-game time and i am 11th Prestige.

I playing almost the full 48 hours of each double xp days and prestiged twice every day.

Thats how easy it is if you play search and destroy.

Search and Destroy gives you massive EXP, especially with Double Xp. (If you do good)