After some delays, Halo developers, 343 Industries are finally released a patch today that promises to fix those matchmaking issues, among other things. You can find the complete patch notes here.
Halo: The Master Chief Collection will get an update today, that will address problems with the campaign, user interface and some party issues with matchmaking.
Yesterday, Halo: The Master Chief Collection developer 343 Industries executive producer Dan Ayoub, written an open letter to all players about the matchmaking problem that was plaguing the series.
As a result of thematchmaking problem affecting The Master Chief Collection, the developers has postponed the beginning of the Halo Championship Series.