Halo 5 Guardians, Available?

Hello all halo community, in the last 12 hours I’ve seen some gameplays on Twitch (only the title of transmission) and I was thinking about it…Supposedly Halo 5:Guardians would be available on october 27th, the pre-order on Xbox let you install the game one week after BUT NOT PLAY IT, so What are they doing to play Halo 5? I can’t understand why they can play it 2 WEEK BEFORE!!! I don’t know but that is an injustice, I know that I’m not the only one that thing that isn’t?

I’m sorry my bad English I’m still learning. Greetings from México.

the gameplay you’ve seen are from people who got the game early on purpose for gameplay reviews. it’s unfortunate so much campaign has been posted but it happens. it will be available to everyone the 27th! happy hunting.

They can play it early so they can write a review of it. 343 also gave them permission to stream a couple of levels.