Connectivity issues with Halo: The Master Chief Collection have lead to the cancellation of one of the game’s eSports tournaments.
Cup #1 of the second season of the Halo Championship Series is an online cup that relies on The Master Chief Collection’s party/invite system to function. 343 has had to cancel that cup over the weekend due to connectivity issues with the game.
Two brackets were scheduled to take place last weekend. The Saturday bracket was played fine, but the Sunday bracket is what encountered these issues. Which of course resulted in developer 343’s decision to cancel Cup #1.
We're aware of and investigating party joinability issues. As a result, we'll be canceling HCS Cup #1, and apologize for the inconvenience.
— Halo (@Halo) April 26, 2015
By most accounts, the last two patches eliminated all party/invitation issues and introduced ranks, but it looks like the most recent ranks patch may have had something to do with it.