That’s a JTM45 6V6 revision of his original superplex that’s a ground up new design of his original JTM-45, not a new metroplex.
People on the metro groups are holding out thinking George will do the same type of design but on a 1959 plexi instead of a JTM-45. No official announcement has been made yet though.
George does amazing work. I would not be waiting anytime soon for a new metroplex though. He’s a perfectionist and a one man job. You’ll be waiting a while.
The original metroplex can already do 50W/100W and also has a dropped B+ mode that adjusts bias on the fly like quickrods. I had zero problem getting good bedroom volumes if I wanted it. It was/is also one of the loudest amps I’ve played except for my Bogner 101B.