August 31st ? What is it all about?

Games Other Halo
1

I just saw a GIF on Halo and Major Nelsons Twitter for something about August 31st ??? Does anyone know what it means?

2

Ok for those unaware.
https://twitter.com/Halo/status/638109002698592257….
https://twitter.com/Xbox/status/638169443219042304….
https://twitter.com/majornelson/status/638199562809778176.

The most interesting thing is that its called the Mission Briefing.
So its highly possible this is just a trailer.

Now a better place to discuss this is here. In the Halo 5 part of the Forums as its related to Halo 5.