Bleeding Cool was the first to break the news (hashtag #NYCC2017Speculation) that Matthew Rosenberg would be doing an X-book as part of Marvel Legacy. Bleeding Cool also broke the news that Rosenberg's book would be called Phoenix Resurrection with Lenil Francis Yu, bringing Jean Grey back from the dead. Marvel officially confirmed Bleeding Cool's scoop today by announcing that very book.
Additionally, Rosenberg will now be a Marvel EXCLUSIVE creator. Rosenberg posted on Twitter:
However, for those worried that the indie darling creator of books like 12 Reasons To Die, We Can Never Go Home, and 4 Kids Walk Into A Bank has sold out, have no fear. Don't be fooled by the Marvel EXCLUSIVE contract he got, he's still, he's still Matty from the block: