As you already know, 921 and CZ-9 are the two upcoming heavy launcher of CASC in this decade.

The following are based on the recent presentation of Long Lehao where a number of new CASC development is outlined.

921 is considered as a further development of CZ-5. It will be developed into two version of man rated rocket, one for LEO mission, and one for lunar mission. The LEO version is expected around 2025 when the phase 2 of CSS will commence, requiring potential transportation of up to 6 crew using the 14 ton next gen spacecraft. This version will not have strap on boosters. The lunar version is dubbed as CZ-5DY, launching the 21 ton lunar spacecraft and the lunar lander in a separate launch. It seem there's a bit of compeition with CZ-9 on the manned lunar mission. I guess the concept will still evolve.

Evolution of CZ-9. The 2011 edition is envisioned to have three configuration: 140 ton CZ-9 with four boosters, 100 ton CZ-9A with two boosters, and 50 ton CZ-9B with core stage. The 2021 edition of CZ-9 will be capable of 150 ton with only the core stage. The difference is the use of 16 YF-135 cluster in the core stage providing the same lift off thrust of 5760 ton as the original CZ-9 with four boosters. Without the dead weight of the four boosters give it additional 10 ton payload.

YF-135 is a 360 ton thrust engine, will be developed based on YF-130, the 480 ton thrust engine developed for CZ-9.

Illustration of the three configuration of CZ-9, CZ-9A, CZ-9B.

The 2021 edition of CZ-9 is apparently influenced by 921, using cluster of engine. Words are that the redesign has first stage vertical landing recovery in mind, which I believe is equally apply to 921 as well. VTVL will be demonstrated first on CZ-8.

CG of CZ-9 2021 edition launch.

Beside manned lunar mission, a potential use of CZ-9 is to construct SSPS aka Space Solar Power Station. Orbiting on GEO, every square meter of solar panel can generate 1353 W of power. The rational is based on the calculation that a 1 km wide array wih 100% conversion efficiency will generate in a year the equivalent of the power generated by total oil reserve on Earth. Personally I'd love to see CZ-9 being used to launch a 8-10 m wide, 140 ton space station module as a life extension to the CSS after 2030.

Future prospect of Chinese aerospace transportation system. Reusable technology from grid fins recovery control, parachute recovery, vertical landing recovery, to horizontal landing recovery will be in development in this decade.

Horizontal recovery technology development roadmap in 3 steps plan, VTVL & VTHL around 2025, rocket powered HTHL around 2030, RBCC HTHL reusable around 2040.

Tengyun orbital spacecraft releasing satellite was tested last year.

Tengyun sub-orbital vertical launch horizontal landing was tested yesterday.

Tengyun's target: launch weight 180 ton, 2 ton LEO payload; first stage RBCC, second stage rocket power; horizontal landing.