It looks like Microsoft is sneaking in one more group of testers before it unleashes the Halo 5: Guardians beta on the rest of the video game buying public later this month. Messages sent out to Xbox One owners who have a console in the Xbox Preview Program indicate they’ll get to play the Halo 5: Guardians multiplayer beta tomorrow.

All told, the process is a bit arduous. Xbox One owners who are still in the Preview Program should have received a message directly to their console telling them of the early access event. This early beta will last the entire weekend. Participants will need to redeem two codes over Xbox Live to successfully get in, it appears purchasing Halo: The Master Chief Collection isn’t a requirement for beta participants like it is for everyone else.

As these messages were going live, so too were details from Xbox Wire about the Halo 5: Guardians beta that everyone else will get to participate in beginning December 29th. 343 Industries plans to roll out new content to the beta each week. Overall, there’ll be 7 new maps, new modes and a new ranking system making an appearance during the three-week event.

The Halo 5: Guardians beta will end for Master Chief Collection buyers on January 18th. The final version of the game launches in Fall 2015. To get into the Xbox Preview Program you need to be invited by a Preview Program participant. Members also get access to Xbox One software updates ahead of everyone else.