It is the main code project I am currently working on. I don’t think we can attach any specific date, there is still some un-entanglment of accumulated technical debt in the API to happen. I really really hope to see first pixels of multiple passes seen very soon!
We are trying to tag all related PR and commits with the task, so you can follow the development in this task: #108618 - Viewport Compositor: Render passes support - blender - Blender Projects