Post-quantum cryptography: what comes next?

This month, a major milestone in post-quantum cryptography (PQC) has been reached: 3 algorithm standards (ML-KEM, ML-DSA, SLH-DSA) have been published by NIST, the US national standards organisation. The NCSC have updated our PQC white paper to reflect this milestone.  While the core technical messages of the paper remain unchanged, we know that many of you want to understand the next steps in the national migration to PQC.