Elon Musk’s days as Twitter CEO are now numbered, with the beleaguered billionaire announcing Thursday that he’s hired another executive to take over the role he’s held since purchasing the social media company in October. Musk says the new CEO, a woman he didn’t name, will be at the helm of Twitter in six weeks. The Wall Street Journal later reported the mystery pick is NBCUniversal’s current head of advertising, Linda Yaccarino, who is currently in talks to take the top spot at Twitter. Musk says he’ll stick around as the company’s executive chair and chief technology officer, which will oversee “product, software & sysops.” The change comes as Musk has been heavily criticized for making sweeping changes to Twitter on a whim, scaring off advertisers and hurting the platform’s credibility by wiping out account verification.