They've always leaned towards Friday morning drops for each major promotion within Madden 22 Ultimate Team, and they may even get things going earlier than Mut 22 coins this week or the following.
Whatever the case, we'll probably see the announcement on a Wednesday edition Good Morning Madden, get an announcement of the program with all of the players on next morning's Thursday edition of Good Morning Madden, and that'll culminate in the release of the program at the beginning of Friday. It could be that the first drop as early as Dec. 3, 2021, however, they've typically waited to a little later in the month to start things off thus the most likely date appears to be December 10 2021.
One thing you can count on out of Zero Chill or any possible December MUT Promo that's announced in the coming days, is that you'll get brand new cards in Madden 22 Ultimate Team. The games usually come with other challenges and missions and all of them revolve around a group of new cards that players can push to add to their own Ultimate Team.
The precise selection of the players that will be selected is a challenge as it is possible to vary but Zero Chill has had a variety of current and former players within the group before. There will likely be a few legendary players and some current young players in the top of the lineup to ensure that things are balanced but the rest of the lineup will change based upon the teams' current roster.
There is also the possibility of coming back Snow as currency, in conjunction with promos like Ghosts of Madden and Snow Beasts, or the inclusion of buy Madden 22 coins the Presents mechanics that Zero Chill played in MUT last year.