https://finance.yahoo.com/news/facebook-send-cambridge-analytica-data-040215882.html

Reeling from its worst privacy crisis in history — allegations that this Trump-affiliated data mining firm may have used ill-gotten user data to try to influence elections — Facebook is in full damage-control mode. CEO Mark Zuckerberg acknowledged that he made a "huge mistake" in failing to take a broad enough view of what Facebook's responsibility is in the world. He's set to testify before Congress on Tuesday and Wednesday.

In prepared remarks released by a House committee, Zuckerberg said the company has notified all users affected in the scandal. Since the remarks are for Wednesday morning, this means everyone who was affected should see a message by then.