So if you check the credits for Artifact, Valve's latest game release, you can find Erik Wolpaw's name in the list of Valve employees, which suggested that he had rejoined Valve at some point before Artifact came out. He had previously left Valve in 2017 around the same time as Jay Pinkerton (since also returned to Valve) and Chet Faliszek (now working at Bossa).
GabeN confirmed as well. Valve is gearing for a new announcement? A lot of writers returned to Valve in the last year.