https://wccftech.com/ubisoft-shares-the-hidden-ones-info-qa/

The Hidden Ones will be the first of two story expansions coming to Assassin’s Creed Origins as part of the Season Pass.

Due to release on January 23rd, it’s set after the events of the main game. Ubisoft provided a new official developer Q&A to share more information on this expansion; you may check it out below.