While writing this question, I was directed to the question Why doesn't SpaceX plan on doing anything new on IFT-6? The top answer basically says it's because Block 2 is totally different.
They now have a completed Block 2 ship, but it's only slated for IFT-7. Why?
TLDR: The first Block 2 starship is ship 33, which is not ready to fly.
Ship 33 has recently been fully stacked, but that doesn’t mean it’s finished. It still needs its engines installed (suspected to be V3 engines, though this hasn’t been confirmed by SpaceX yet) and other flight features. Additionally, it still has to go through testing at Massey’s. There, it must complete a cryogenic proof test (WDR) & later a static fire. NSF in their latest update noticed that the 4 point lifter has been brought to mega bay 2 for installation. This could very well be for S33, which may be soon brought on a transporter to be tested at Massey’s.
Even if Ship 33 is moved to Massey’s soon, it will likely need at least a month, if not longer, to complete everything before flight. In his recent video, What About It mentioned that SpaceX may be targeting as early as November 11th for IFT-6. While the launch probably won’t happen that soon, a November launch is still possible. Ship 33 probably needs at least a month and possibly longer (especially if V3 Raptor engines are installed). Therefore having it ready for a November launch is unlikely.
Ship 31, which is planned to fly on IFT-6, is one of the last Block 1 ships. The others include Ship 20 (the first with a full heat shield, now completely outdated), Ship 26 (flapless and heat shield-less, possibly an old prototype for orbital refueling or moon landing—there's been so much speculation about it, that we can only guess what it’s purpose was for), and Ship 32, which is incomplete and sitting in the rocket garden for a while, likely awaiting scrapping.
Ship 31 was rolled to Massey’s and conducted a WDR on May 11th, got too excited and accidentally experience a few "fireworks" on its side due to an electrical fire - pun intended. A successful WDR followed in July, and a successful static fire occurred in mid-September. With all of this completed, Ship 31 is the best candidate for IFT-6.
