Mistral Large 4 and Reflection Beam: planning self-hosting around unreleased open weights

Mistral Large 4 and Reflection Beam are previewed, but their open weights are not yet available for self-hosting.

Mistral has said its weights will drop at the end of October, and Reflection has promised Apache 2.0 weights this month, according to launch posts circulating on X. A guide on evaluating and self-hosting these models argues that announced but unreleased weights should be treated as a conditional migration dependency rather than a current option.

API previews can be trialed immediately, but the source notes they do not prove that a downloaded checkpoint will behave the same way. The guide's basis is an announcement by Mistral of Mistral Large 4 on 6 October; the reporting does not establish the release outcomes themselves.