https://www.polygon.com/2018/11/26/18112534/red-dead-redemption-2-rdr2-online-multiplayer-beta-release-date

Red Dead Redemption 2’s online multiplayer mode, Red Dead Online, will go live on Tuesday, Nov. 27, Rockstar Games announced today.

Rockstar will launch Red Dead Online in beta form on Nov. 27, and it will initially be accessible only for owners of the Ultimate Edition of Red Dead Redemption 2. The following day, the beta will open up to those who played Red Dead Redemption 2 on its first day of release. On Thursday, Nov. 29, those who played the game in its first three days of release will get access. Then, on Friday, Nov. 30, online multiplayer will open up for all Red Dead Redemption 2 players.