Yes, I remember what he posted; Viettel's calculation for the INS drift rate of a 1800 km ballistic missile.
Based on the latest unofficial leak, after being stuck for 5-6 years at the 600 km range, Viettel has been able to break the technical barrier by resolving the mathematical calculations for the inertial navigation system drift error algorithm and extend the VCM-06 LACM to way over 1000 km now. This is a major breakthrough as it will also allow Vietnam to extend the range of our ballistic missiles, and long-range suicide drones