A optimization patch is under review, expected to provide a noticeable performance increase here: ⚙ D14645 Cycles: Apple Silicon optimizations (~40% uplift on M1 Max)
As such, it’s possible this patch could be implemented soon. However, based on these rendering meeting notes (link) it seems like some adjustments are expected to be made before the feature gets merged into Cycles. And I don’t know how long it will take to make those changes and so I can’t tell you when this patch will be accepted and merged with Blender.