Thanks for posting. I just checked my Monetization options and I don't see anything new.
I just checked the stats for KSIOlajidebt using the Social Blade website and they have tremendous traffic!
1 million views a day, 30 million a month, and a million subs!
Maybe that advertising option will only be available to YouTube channels who are part of larger networks or those channels with a certain threshold as far as total subscribers or total views. Maybe I don't have that option because I am not part of a network, I only have 13,000 subs, and only 5 million views a month.