The Overwatch closed beta will re-open on February 9th after an extended break that began back in December.
Blizzard is to introduce an "all-new progression system," as well as two new maps and a new game mode. The developer has also made hero balance changes and a "variety of private game updates," including full A.I. matches.
Naturally, those who had access to the closed beta before will have access once again. Blizzard intends to let more people in as the trial period continues, so if you're interested you should opt in.
Overwatch is yet to get an official release date. It is expected sometime during Q2 2016 on PC, PlayStation 4, and Xbox One.