Hwasong-15A (?) -- Why the HS-15 was changed ?

Norbert Brügge, Germany

2022, November 03
-- North Korea has launched an intercontinental ballistic missile (ICBM) from the Sunan area in Pyongyang  and flew about 760 kilometers at an apogee of around 1,920 km at a top speed of Mach 15, according to South Korea's Joint Chiefs of Staff (JCS).

There is now a photo of the launch. It shows a shortened HS-15 with a modified WH. It is unclear why both the first and second stages were shortened. One reason may be that the HS-15 is unsuitable as an ICBM and really only corresponds to the upper stages of a future Unha-X (SLV) and the HS-15A (?) is optimized as an ICBM.