“Game on,” Elon Musk’s hand-picked successor tweeted, a week after thanking her new boss for the job leading the social network.

Her post linked to a TechCrunch article about Meta-owned Instagram’s Twitter clone. That article includes a tweet by Lia Haberman, author of social media newsletter ICYMI, showing what is reportedly a screenshot of the new app.

Meta reportedly included the screenshot in an email sent to a select group of creators. Fortune reached out to Meta for comments but received no immediate reply.

According to Haberman, who said she spoke to a creator who received the email, Instagram’s Twitter competitor could be released in late June. It will be a decentralized app “built on the back of Instagram but will be compatible with some other apps like Mastodon.” She added there’s a single sign-on with your Instagram username and password; you can sync up with your existing followers; and your handle, bio, and verification will carry over from Instagram.

Matt Navarra, a social media consultant, received some of the same information and shared it in a May 12 tweet.

Meta will trail other Twitter alternatives like Mastodon and Bluesky in terms of timing, but it will have one enormous advantage: access to billions of users through Instagram, Facebook, WhatsApp, and Messenger, all of which it owns.

The competition from Meta adds to the difficult job ahead for Yaccarino, who also must persuade advertisers who reduced their activities on Twitter to take a second look. Many feared a spike in objectionable content under the ownership of Musk, a self-described “free-speech absolutist.” 

On that front, Yaccarino, NBCUniversal’s former head of advertising, is already having a positive impact. GroupM, one of the world’s top media agencies, is “cautiously optimistic” about Yaccarino’s appointment and has told clients it no longer considers Twitter “high-risk,” according to the Financial Times.

While Musk has pushed for more subscription revenue, Twitter has long relied on advertising as its main source of revenue. Wedbush Securities Managing Director Daniel Ives told Reuters that Musk’s appointment of Yaccarino was a “home-run hire,” noting, “This is someone who’s going to be much more aggressive on advertising.” 

She’ll also be unafraid to challenge Musk, judging by her performance interviewing him last month onstage at a Possible marketing conference in Florida. She aggressively questioned him about the concerns of advertisers and even got him to promise he would “aspire to tweet less after 3 a.m.” 

Now Yaccarino, who some believe is in a glass-cliff situation that other female CEOs have encountered, faces the prospect of competing head-on with Mark Zuckerberg’s Meta, a formidable rival with proven social media chops. Game on indeed.