Adding a little color here... There are already code points registered for pure ML-KEM on the basis of the draft.
The hybrid code point you reference is "preliminary" in the sense that when the RFC for hybrid ECC/ML-KEM is published (it's already been approved, https://datatracker.ietf.org/doc/draft-ietf-tls-ecdhe-mlkem/), it will replace the reference in the registry. However, it will have the same code point and the same semantics. If, for some reason, the IETF were to change the semantics, a new code point would have to be assigned for interop reasons.
> […] "preliminary" in the sense that when the RFC for hybrid ECC/ML-KEM is published […]
Yes, sorry, I was just covering against people nitpicking on the document status :)
Actually… what would even be the result of the pure MLKEM document getting dropped by the IETF? I guess the entries would temporarily be marked deprecated or something, until another reference is made available somewhere, describing the same behavior? I'm not sure what procedural blockers this might run into but my general sense is that the IETF & IANA wouldn't "block off" the already allocated codepoints from being specified elsewhere (or allocate new duplicate codepoints) so long as the behavior is identical.