This is just my personal opinion here: Long's design presents a future out look for a starship-style recoverable super heavy rocket. Current news all point to the fact LM-9 is still being worked on as the 2011 design.What are these engines going to be used for now? On 24 June 2021, the chief designer of the Long March series, Long Lehao, presented a new design of Long March 9 which uses 4 new 120-tonne hydrolox engines for the second stage, instead of 2 YF-90 engines used in earlier design. Or are they going to build two completely different types of Long March 9?
In fact this just came out. 9.5 meter bulkhead rings. Obviously for the core booster stage for the 2011 design.